Honda Odyssey and Pilot Forum

General Category => Pilot FL400R => Topic started by: PilotSniper on November 29, 2005, 12:16:30 AM

Title: Coolant Problem - What's Next???
Post by: PilotSniper on November 29, 2005, 12:16:30 AM
Okay guys, here's a doozie I really need help with...

Once apon a time, I wanted to get my Pilot back up and running after my lower back fiasco, so I decided to get a couple of things fixed and some maintenance done. I had a problem with my reserve fuel sensor, which wasn't working, and another problem with leaking coolant, so I figured I'd tackle these problems head-on.

Regarding the reserve fuel sensor, I ordered a replacement sensor. No big deal.

Regarding the leaking coolant, I looked under the Pilot with the engine cranked and saw that I had a shot mechanical seal (leaking coolant profusely through the cheater hole under the water pump) which, I believe, was caused by a kinked radiator hose that was going to the head. The hose used to curve nicely into the top of the head, but with time, it developed a kink which I believe caused the coolant to stop flowing, which, in turn, caused the mechanical seal to overheat and crack in two places. Since I was changing hoses and getting deep into the whole cooling system, I decided to change out the radiator cap, too. It was looking rather ragged after all of these years of use.

The rebuild began with the removal of the fuel tank. Not only was the reserve fuel sensor shot, but I noticed that there was a small amount of surface rust inside the fuel tank. I took some washers and dumped them into the fuel tank, along with some POR-15 metal ready conditioner in order to remedy the surface rust situation. The tank came out great, so I changed out the bad sensor for the good one and completed the task at hand.

Next, I had to tackle the right side cover in order to change out the mechanical seal. Not only did I change out the mechanical seal, but I put a new water pump shaft in as well. Call it preventative maintenance or whatever you like, but it helps me sleep at night.

Either way, I put everything back together and decided to do some maintenance work. Not only did the right side get new oil, but the case got an oil change as well.

Here I was, all done with everything I set out to do, but things didn't work out as good as I had hoped. On the maiden voyage out, my engine quit 30 feet from the house. Fortunately, the culprit was a defective spark plug and a new one cured the illness.

Next, since I had cleaned out the tank, the two subsequent fuel tank flushes apparently weren't enough. A few little (and I mean little) rust particles were enough to cause my carburetor's overflow tubes to go into fuel overflow during my second test run. Fortunately, a thorough cleaning of my carburetor's float bowl was all she needed to squash that issue.

Lastly, this is the problem I need help with. I fill the radiator with coolant to the top, purge the air by throttling the engine, then top off with coolant again. If I take her out for a hard run, she'll start to overheat only a few minutes into the run. When the Digatron yells at me, I shut her down and take a peek into the radiator. By this time, it's usually half empty. The only leak point is the pressure relief hole built in to the radiator cap. This is only supposed to spew when the cooling system reaches 20psi. To test this, I put a gauge onto the small radiator hose that used to carry coolant through the OEM carburetor's heating system. I pressurize the system to 15psi without any leakage of pressure. As soon as I hit 20psi, the pressure relief hole in the cap does what it's supposed to do and spews coolant.

After the repair of the mechanical seal, I have a beautiful stream of coolant flowing through the cooling system. If you peek into the neck of the radiator, you can see the coolant flow coming back in from the head's return hose.

After the pressure test, I have concluded that I don't have any leaks in the cooling system. I have also concluded that the radiator cap is working as per the manual's specifications.

I have checked and rechecked all the hoses and can certify that there are no hoses that are kinked or pinched in any way.

I have flushed the radiator with a garden hose from the top to the bottom and I don't have any obstructions in the radiator.

I have flushed the entire cooling system via the bottom radiator hose with the garden hose, causing fresh water to flow through the entire cooling system (minus the radiator) and it comes through successfully, which indicates that there are no obstructions in the cooling system.

Why, then, when my engine heats up during a hard ride, does the pressure of the water exceed 20psi and cause the radiator cap to go into "pressure protection mode" and spew coolant not only into the reserve tank, but out through the cap's hole?

Has anyone ever encountered this problem and what do I do to remedy the problem?

Can anyone think of something that I haven't tried yet?

As you might imagine, this one is really kicking my ass!

Thank you in advance for your help!!!
Title: Coolant Problem - What's Next???
Post by: PilotHawK on November 29, 2005, 01:05:16 AM
Is there any debris floating in the coolant? Something that looks a little like pepper maybe? I could be you have a head gasket leak and the cylinder pressure is pressurizing the cooling system. The bad thing about this is that you may not develop the head gasket leak until the engine warms up. One thing you can try is to pressure test the engine and check for air bubbles in the radiator. I know this is not what you wanted to hear, but its the only suggestion I have.
Title: Coolant Problem - What's Next???
Post by: ludedude on November 29, 2005, 01:21:18 AM
Yup, if you ran it with lack of coolant, I bet your head gasket is gone and possibly your head is warped....well yours is..I mean the pilot head  :P
Title: Coolant Problem - What's Next???
Post by: PilotSniper on November 29, 2005, 01:47:14 AM
Thanks guys! I think we might have a winner here!!! The fact that the radiator hose was originally kinked caused the engine to overheat, which tapped-out my mechanical seal. All that is fixed, but the remnant of the original overheating must be exactly what you are describing. I took a quick look into the radiator just now and I've got the dreaded floating pepper indicator. I guess my next step is to order a head gasket and tear that puppy open. Well, it's not the news I was looking for, but at least it gives me a direction in which to go along with some badly needed hope for an end to this problem. I was really, really stumped on this one!

Since I've probably warped the K-Fab head that's currently installed (or at least the dome) and can't get a replacement for it, what head is the popular recommended replacement, along the lines of the K-Fab head (i.e. two-piece design, centered dome, etc.)??? If such an animal exists, where can this head be purchased???

Thanks again guys!!! I appreciate the help!!!
Title: Coolant Problem - What's Next???
Post by: PilotHawK on November 29, 2005, 02:21:27 AM
You can lap the head flat again. Using a piece of 220 or finer grit wet/dry sandpaper taped to a 1/4" or thicker piece of plate glass placed on a solid surgace (a lap stone would do better, but I doubt you have one at home) Tape the sandpaper to the glass and spray it liberally with WD-40. Using slow circular or figure 8 motions you can flatten the head. If you use machinists blue dye, you can see the high spots clearly as they are sanded off. Of course if you don't want to do any of this you can take the head to a machine shop and have them resurface the head for you. I bet you could even get Moskito to resurface the dome for you.

If the dome is "warped" most likely the top of the jug is out too. You may be best served by pulling the jug and having it machined as well (or lap it as previously mentioned).
Title: Coolant Problem - What's Next???
Post by: PilotSniper on November 29, 2005, 03:16:41 AM
Hawk,

I don't think I'll be lapping anything in my lifetime, but thanks for the lesson!

I'd rather send my stuff out and have it machined. Also, I don't want to put Skeeter out of his way, so if there's another replacement head that has the qualities of the one he created, I'll look into getting one (if I find that I need it).

As for the cylinder, is there an alternative to spending $300 for a new one, then sending it over to ATV Racing and spending another $410 to have it ported and polished??? I currently have the ATV Racing modded jug, like it, and would like to continue to use it (unless I can't, due to the possibility of excessive warping). I'd like to see what my options are. Any advice?

I've used Bill Moeller's services at Bore-Tech in the past with great success. I know I can get some machining done there, as well as having him fit the correct Wiseco piston to my jug, but does anyone know if he can lap the head and jug, if needed?

I apologize for all of the questions, but I know you guys have probably "been there and done that".

Thanks again!
Title: Coolant Problem - What's Next???
Post by: PilotHawK on November 29, 2005, 03:46:20 AM
If you send me the jug and head I'll take care of it for you.
Title: Coolant Problem - What's Next???
Post by: PilotSniper on November 29, 2005, 10:51:49 AM
Quote from: "PilotHawK"
If you send me the jug and head I'll take care of it for you.


Thanks Hawk! That's cool for you to offer!!!

Let me get some time so that I can dig into the top end and see what surprise awaits. We'll see the damage and take it from there. I hope it's not bad... :cry:

Thanks again for the offer!
Title: Coolant Problem - What's Next???
Post by: ludedude on November 29, 2005, 01:34:30 PM
Lapping's not that big of a deal Vic, you did a complete rebuild...I'm confident you can perform the needed lapping ;) I be surprised if you cannot use the head and cylinder again, fear not, I'm sure they're useable again after some massaging ;)
Title: Coolant Problem - What's Next???
Post by: PilotSniper on November 29, 2005, 05:46:36 PM
Quote from: "ludedude"
Lapping's not that big of a deal Vic, you did a complete rebuild...I'm confident you can perform the needed lapping ;) I be surprised if you cannot use the head and cylinder again, fear not, I'm sure they're useable again after some massaging ;)


Thanks for the vote of confidence bro! It's always my fear of going into uncharted territories that makes me shy away from all of the "complicated" stuff. I guess you're right, though. Had I not jumped into the complete rebuild, I wouldn't have learned how to do any of the things I now know how to do. I'm trying to position my days this week to see if I can get some time to do a teardown of the top end and see what I'm really dealing with. After PilotHawk and you enlightened me, I'm 100% certain that this is what's going on. I guess we'll find out soon enough how bad the damage actually is.

No worries! I'll keep you posted and, hopefully, I'll be taking a pic of a bad gasket and not a badly warped head and/or jug!!!
Title: Coolant Problem - What's Next???
Post by: ludedude on November 29, 2005, 06:47:16 PM
take pictures as soon as you remove the head...don't wipe the gasket or the head/jug...you can look for signs of the coolant leakage on them ;)
Title: Coolant Problem - What's Next???
Post by: PilotSniper on November 29, 2005, 07:26:10 PM
Will do! Trust me, I want to get rid of this problem in a BAD way!!! :(
Title: Coolant Problem - What's Next???
Post by: Tman on November 29, 2005, 07:59:15 PM
Notice Lude's familiarity of what to do exactly?  :roll:
Title: Coolant Problem - What's Next???
Post by: PilotSniper on November 29, 2005, 08:09:41 PM
Quote from: "Tman"
Notice Lude's familiarity of what to do exactly?  :roll:


Haha!!! Are you implying that "he's been there and done that" already??? :wink:

If so, THAT'S EXACTLY WHAT I NEEDED BECAUSE I COULDN'T TAKE ANOTHER DAY OF THIS UNCERTAINTY!!! Call me crazy, but I never thought I'd be happy about having to tear into my engine!!! Wooohooooo!!!  :mrgreen:
Title: Coolant Problem - What's Next???
Post by: PilotSniper on November 30, 2005, 12:27:28 AM
Here are the pics I promised. I decided to tear into it tonight after work. What's the sense of waiting to find out the bad news? :lol:

Can anyone see anything abnormal? I tried to find some sort of negative indicator, but my untrained eyes don't seem to find anything. The only thing that struck me as strange was that the dual-layered OEM metal head gasket was warped when I removed it. From memory (although I'm not 100% positive), when I've removed this gasket previously, they have always laid flat. Is there a remote possibility that I might just have a bad gasket??? Also, what are the chances of having a small heat-related crack somewhere down in the coolant-flow area of the jug? I remember seeing something like this online once. This jug has been worked by ATV Racing, so there's less meat in there and more chance of a debilitating stress crack to occur. What do you think???

Please click on each picture to see a larger, more detailed picture.
Title: Coolant Problem - What's Next???
Post by: ludedude on November 30, 2005, 01:36:26 AM
I don't see anything right off that yells "leak here"

What I've seen is....well...it looks like exhaust reside left on the head where it has escaped the combustion chamber to one of the coolant passages.

Take a straight edge and lay it on the top of the jug (in varying orientations) and see if you can slide feeler gauges uner it anywhere (or look for light under the straight edge) Do the same for the head.

I have a long lapping stone that will reach across the cylinder/head. I will black them out with a marker and then rub the surface with the stone, any left indicates low spots. The head you can lay flat on sandpaper..the stone is good for checking the cylinder while the studs are still in ;)

I got away with a new gasket, but lapped the head for a bit of insurance  8)
Title: Coolant Problem - What's Next???
Post by: PilotHawK on November 30, 2005, 01:39:33 AM
Please tell me you did a pressure check first? Also the stud at the 4 o'clock position in the last 2 pics is very corroded. Was this stud this way the last time you put it together? I see a couple of areas that are odd on the head. The area the green arrow is pointing to looks very clean as if it may have been a passage for exhaust gasses to escape into the coolant. and what is on the head where the blue arrow is pointing?
Title: Coolant Problem - What's Next???
Post by: PilotSniper on November 30, 2005, 01:42:09 AM
That's understandable and sounds simple enough. I'll give it a whirl and see if I can add lapping to my resume! :D

Now that I have the jug off, the piston looks good, although it looks like it has more play inside the jug than when I originally installed it. I know that heat brings these things back to tighter tolerances, but do you think I should change the piston, just in case?

Any thoughts?
Title: Coolant Problem - What's Next???
Post by: ludedude on November 30, 2005, 01:48:23 AM
(http://p-o-ps.com/forum/gallery/albums/albumssss/10027/normal_Top%20End%20Rebuild%20-%20Head%20Studs%20Installed.jpg)

clean and shiny on rebuild
Title: Coolant Problem - What's Next???
Post by: PilotSniper on November 30, 2005, 01:50:52 AM
Quote from: "PilotHawK"
Please tell me you did a pressure check first? Also the stud at the 4 o'clock position in the last 2 pics is very corroded. Was this stud this way the last time you put it together? I see a couple of areas that are odd on the head. The area the green arrow is pointing to looks very clean as if it may have been a passage for exhaust gasses to escape into the coolant. and what is on the head where the blue arrow is pointing?


Of course (not)! Now I'm kicking myself in the ass because Odykid loaned me his pressure test kit yesterday and it's sitting right here. Duh!

As for the studs, they were all new after the last rebuild, so the corrosion shouldn't be there.

Regarding the green arrows, I agree with your findings. I just took another look at the actual head and there might have been a weak point right there. Good eye!!!

Regarding the blue arrow, that's just more of the same old stuff that's near each identical section surrounding the head. The camera's flash seems to have given it a different look, that's all.

I'm going to try to measure for flatness on the head and jug tomorrow, as Lude has indicated. Since I don't have an answer to possible warpage on these two parts yet, what do you think about the warped head gasket? Does my memory serve me correctly and should they actually come out flat??? Mine looks twisted as it lays on the floor.
Title: Coolant Problem - What's Next???
Post by: PilotSniper on November 30, 2005, 01:53:21 AM
Quote from: "ludedude"
clean and shiny on rebuild


Hahaha!!! Good find on the pics bro! Hawk, there are the shiny studs I told you about. Wow, that really gets me thinking about the seriousness of the warpage in the top end. Something tells me this is not going to be fun... :cry:
Title: Coolant Problem - What's Next???
Post by: ludedude on November 30, 2005, 01:56:50 AM
It only takes a minute bit out to cause you troubles.
Title: Coolant Problem - What's Next???
Post by: PilotSniper on December 06, 2005, 02:29:18 AM
Well, I took my time, got some 3M 320 Grit Wetordry sandpaper, a can of WD-40, a roll of duct tape and my glass dinner table (the wife was thrilled with that choice :wink: ) and did my first-ever lap job! I want to thank you guys for the insight because I would have never thought of doing this, but it worked like a charm!!!

THE CYLINDER: I took the studs off, cleaned the gasket surface area very well with a rag soaked in lacquer thinner, then took my time painting the gasket surface area with a permanent black magic marker. I taped the sandpaper to the glass table so that the duct tape overlapped the edges of the sandpaper one-half inch. I then gave the sandpaper a thorough spraying of WD-40 and proceeded to lap the cylinder using a circular motion. As you can see by the pic below, the cylinder now has a nice, shiny surface. Fortunately, it did NOT have any warpage, so I cleaned her up and proceeded to the head.

THE HEAD: I cleaned the gasket surface area very well with a rag soaked in lacquer thinner, then took my time painting the gasket surface area with a permanent black magic marker. I gave the sandpaper another thorough spraying of WD-40 and proceeded to lap the head using a circular motion. In this case, the black marker wore off of most of the head's gasket surface area, but remained in the area that PilotHawk pointed out, as well as a ring that went all the way around the edge of the dome. This, as I quickly figured out, is where the high point on the OEM gasket is. That "ring" in the gasket apparently cut its own groove into the head's aluminum. I had to work the head in a circular motion and stop periodically to re-wet the sandpaper with the WD-40. All-in-all, I took my sweet time and the process took a total of 30 minutes. The head was definitely warped from the overheating, but, as you see from the pic, was nice and even by the time I finished the lapping procedure.

Now, I anxiously await the arrival of my gasket set from Service Honda. I'm dying to put this puppy together and give her a whirl!!!

Thanks again for the help guys!!! Once she's put together and tested, I'll (hopefully) be posting that my coolant spewing problem is no longer an issue.

Wish me luck!
Title: Coolant Problem - What's Next???
Post by: ludedude on December 06, 2005, 02:39:14 AM
AWESOME!!!! See that wasn't hard now was it  :D


 :big clap:  :big clap:  :big clap:  :big clap:  :big clap:  :big clap:
Title: Coolant Problem - What's Next???
Post by: PilotSniper on December 06, 2005, 02:42:36 AM
LOL!!! No. You were absolutely correct!!! I told you bro, it's the usual...

FEAR OF THE UNKNOWN!!! :wink:
Title: Coolant Problem - What's Next???
Post by: PilotHawK on December 06, 2005, 08:43:35 PM
Glad to see you are making progress towards the rebuild.
Title: Coolant Problem - What's Next???
Post by: PilotSniper on December 06, 2005, 10:36:47 PM
Quote from: "PilotHawK"
Glad to see you are making progress towards the rebuild.


Thanks Hawk! Just waiting on gaskets now...
Title: Coolant Problem - What's Next???
Post by: ludedude on December 06, 2005, 10:38:22 PM
:bigzzzz:  :bigzzzz:  :bigzzzz:  :bigzzzz:  :bigzzzz:  


ho hum <Sniper twiddling fingers>

 :mrgreen:
Title: Coolant Problem - What's Next???
Post by: PilotSniper on December 06, 2005, 10:40:06 PM
Quote from: "ludedude"
:bigzzzz:  :bigzzzz:  :bigzzzz:  :bigzzzz:  :bigzzzz:  


ho hum <Sniper twiddling fingers>

 :mrgreen:


LMAO!!! Yeah, you're right about that!!! I get all excited when the FedEx truck pulls in at work. Is that wrong in any way? :wink:
Title: Coolant Problem - What's Next???
Post by: ludedude on December 06, 2005, 10:44:02 PM
Not at all  :lol:
Title: Coolant Problem - What's Next???
Post by: Moskito on December 14, 2005, 09:43:05 PM
Quote from: "PilotSniper"
Also, I don't want to put Skeeter out of his way, so if there's another replacement head that has the qualities of the one he created, I'll look into getting one (if I find that I need it).

Domes are a breeze - and I have the material for a few more.  Let me know if you need anything.  (I've not read past this, so you may have already solved the problems).   Please, always feel free to ask me, don't assume that I'll just say no. (:
Title: Coolant Problem - What's Next???
Post by: PilotSniper on December 15, 2005, 09:14:31 AM
Quote from: "Moskito"
Quote from: "PilotSniper"
Also, I don't want to put Skeeter out of his way, so if there's another replacement head that has the qualities of the one he created, I'll look into getting one (if I find that I need it).

Domes are a breeze - and I have the material for a few more.  Let me know if you need anything.  (I've not read past this, so you may have already solved the problems).   Please, always feel free to ask me, don't assume that I'll just say no. (:


As always, you know I appreciate the times you've gone out of your way for me. I lapped everything and I think I'll be okay. I appreciate your offer, but I believe we're good in that department (until further notice). Thanks again, bro!!!

Well, I got my gaskets earlier in the week, but noticed at the last minute that I had a problem that I had originally overlooked. I assumed that the piston was okay, based on a quick visual inspection. I was wrong. Upon closer inspection (right before I was going to put the jug back on), I noticed that the top ring was "sticking" on one side. The bottom ring was "springy", like they're supposed to be. I assume that it's more consequential damage due to the overheat I experienced. Since I've torn everything down and I want to get everything back inline correctly, I ordered another piston. It'll be here tomorrow. Time permitting, she'll be done by this weekend.

I'm hoping that the head gasket leak was the primary problem and that all of this mess gets fixed after I put it all back together. If not, the only other thing that it could be is a hairline fracture deep inside the coolant passages in the jug. That would mean more time, more money and more patience. Let's hope it's just a head gasket...
Title: Coolant Problem - What's Next???
Post by: PilotSniper on December 17, 2005, 07:36:34 PM
UPDATE: I put everything back together this morning, took her for a short spin this evening and everything seems to be back to normal. I'm not going to claim victory on this one until I give her a good, hard run. I'll update again after I get the chance to do just that. Hopefully, I'll be reporting complete success and I can end this thread on a happy note!

Thanks again for everyone's help!!!
Title: Coolant Problem - What's Next???
Post by: PilotHawK on December 17, 2005, 08:00:27 PM
Glad to hear it! I got one back together today too. Seemed to work great after the top and bottom end I redid.
Title: Coolant Problem - What's Next???
Post by: ludedude on December 18, 2005, 08:15:22 AM
I got top end parts on order to redo the top end, (finally, eh PH!) and replace that sanded piston with an OEM Honda one. Hopefully the patrs will show before Christmas, so I can get some running/racing in with Ted  :P  

After Christmas I think I selling the 500 that's in there, the spare 500 that is ready for assemby, and a spare 400.

I'm thinking of trying a set of tracks on the pilot for winter (won't be this winter)....and I want to drop a sled engine in to make up for the increased power consumption the tracks take up. From what I'm reading they're quite the power hogs!  If the engines sell I'll see if I can pick up a sled for the winter...if it's suitable, drive it for the winter then in the spring, begin the transplant.

We'll see  :roll:  Ted thinks I'm nuts...and may convince me yet to stay with pilot power  :lol:
Title: Coolant Problem - What's Next???
Post by: PilotHawK on December 18, 2005, 12:04:02 PM
If I had access to sleds the way you guys do, a transplant would be in order! Just so you know....there's probably nothing wrong with running that sanded piston. You might want to replace the rings and put a light hone on the jug, but at least you know that piston shouldn't stick on you :)
Title: Coolant Problem - What's Next???
Post by: PilotSniper on December 18, 2005, 06:21:06 PM
B, what's a sanded piston? Did you take one with a little damage and fix it???
Title: Coolant Problem - What's Next???
Post by: ludedude on December 18, 2005, 07:35:35 PM
Yes and no  :lol:  Take one wityh a little damage and fix it, yes....me, no...that was PH...told you, you missed a good trip at Coal Creek  :roll:
Title: Coolant Problem - What's Next???
Post by: PilotSniper on December 18, 2005, 09:20:07 PM
Quote from: "ludedude"
Yes and no  :lol:  Take one wityh a little damage and fix it, yes....me, no...that was PH...told you, you missed a good trip at Coal Creek  :roll:


LOL!!! You did a top-end job at Coal Creek? Man, that's hard-core stuff right there!!! :wink:
Title: Coolant Problem - What's Next???
Post by: Ozpilot on December 18, 2005, 09:52:28 PM
"You did a top-end job at Coal Creek? "


There's an understatement!!!
Title: Coolant Problem - What's Next???
Post by: ludedude on December 19, 2005, 05:55:17 AM
:lol:  :lol:  :lol:
Title: Coolant Problem - What's Next???
Post by: PilotSniper on December 19, 2005, 01:17:17 PM
LOL!!! I guess I had to be there...
Title: Coolant Problem - What's Next???
Post by: Moskito on December 22, 2005, 09:42:03 AM
Quote from: "PilotSniper"
Quote from: "ludedude"
Yes and no  :lol:  Take one wityh a little damage and fix it, yes....me, no...that was PH...told you, you missed a good trip at Coal Creek  :roll:


LOL!!! You did a top-end job at Coal Creek? Man, that's hard-core stuff right there!!! :wink:


Wasn't it more like many top end jobs that weekend???  Lude's Pilot had the jug off more than it was on...
Title: Coolant Problem - What's Next???
Post by: ludedude on December 22, 2005, 10:58:40 AM
Quote
Wasn't it more like many top end jobs that weekend??? Lude's Pilot had the jug off more than it was on...


off more than on...you may be right!  :lol:  Definitly less run time than wrench time