C&C
Well-known member
Two suspected head gaskets. Let's keep this in mind; suspected until proven. So currently, no head gasket failures. I'm not denying the possibility but wouldn't want to assume anything either.
Low compression. Head gasket failure?
- Thread starter teacherman
- Start date
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3dogs
Well-known member
Nowhere have you mentioned the percentage of leakdown from your testing. A leakdown tester usually has 2 gauges (one that measures the air pressure from the air supply (air compressor) and the other that measures the pressure in the cylinder. To get a reading you use the percentage of cylinder pressure vs. the supplied pressure. In general, leakdown percentages of not more than 20% are OK. It's more important to compare all the cylinders to each other. A blown head gasket will be easy to find using this method. From what I've read in this thread I do not think that you have a head gasket issue unless more testing is done to confirm.
A simpler test is a cranking vacuum test. Connect a vacuum gauge to each intake track (use the same ports for syncing the throttle bodies). Crank the engine over a few times while watching the needle on the gauge. The needle will pusle as the cylinder is on its intake stroke. The pulses should be about the same between cylinders. If you have any type of cylinder sealing problem, that cylinder will not pulse the vacuum gauge needle the same as the other cylinders.
At a minimum you should perform the cranking vacuum test to verify a blown head gasket (this is highly unlikely unless the engine was run low on coolent and overheated).
I have to concur with other posts about not possibly being a head gasket issue.
Dcarver has some significant issues with water in the motor (maybe head gasket, maybe worse), it's in the oil and ingesting it in the combustion chambers, but it still fires up!
Your motorcycle doesn't start suddenly, why... Not sure, but has there been any other indication for a head gasket starting to fail? I can't believe a bike with 64K living in SoCal and only ridden semi-often just blows a head gasket without some sort of significant event, such as, over heating, loss of coolant, extreme cold, etc. Have you done just a standard compression test? That speaks volumes. It's either good or not. At least you can see the difference between cylinders. I can't believe they are all real low and it's the HG. How would it affect all of them? It should really only affect one or two cylinders. You can start the oil squirting deal if a cylinder reads low and even if it doesn't help, it could still be a valve issue.
I mean geesh, Has anyone worked on the valve adjustment lately? Did your timing chain break? Did the cam chain skip teeth, or... I'm not sure why you've zoomed into the head gasket like this without any indication of coolant leakage outside the motor or in the oil or combustion chamber.
Just sayin' and trying to help.
Good luck.
Dcarver has some significant issues with water in the motor (maybe head gasket, maybe worse), it's in the oil and ingesting it in the combustion chambers, but it still fires up!
Your motorcycle doesn't start suddenly, why... Not sure, but has there been any other indication for a head gasket starting to fail? I can't believe a bike with 64K living in SoCal and only ridden semi-often just blows a head gasket without some sort of significant event, such as, over heating, loss of coolant, extreme cold, etc. Have you done just a standard compression test? That speaks volumes. It's either good or not. At least you can see the difference between cylinders. I can't believe they are all real low and it's the HG. How would it affect all of them? It should really only affect one or two cylinders. You can start the oil squirting deal if a cylinder reads low and even if it doesn't help, it could still be a valve issue.
I mean geesh, Has anyone worked on the valve adjustment lately? Did your timing chain break? Did the cam chain skip teeth, or... I'm not sure why you've zoomed into the head gasket like this without any indication of coolant leakage outside the motor or in the oil or combustion chamber.
Just sayin' and trying to help.
Good luck.
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FJRay
Well-known member
And the mental masturbation continues. I haven't counted the number of us that have tried to point this person in the right direction. I guess after the head gasket isn't bad the it will go cheap as a basket case :angry2:
dcarver
Well-known member
teacherman
Member
Back to methodical tests and square one. Will keep board posted. Thanks to all who have contributed. As to the heating issue, no, it never got above three bars. The bike has gone through summers commuting my rear end 2X-3X per week; 100 mi round trip with splitting lanes, stop lights, and once the traffic clears, 80mph cruise to the house, in at times, triple digit temps. Never overheated from what I could tell. Two/three bars on temp gauge. Anyway, back to square one with the steps contributed.
FJRay
Well-known member
carlson_mn
Well-known member
Make sure mice didn't chew any wires... just to check simple things first after sitting for weeks. Good luck.
bucky
Well-known member
Once after living in my house for 8 years, I started my car and it ran rough and the emission check light went on. Thought it was fuel, bad plug, etc. Anyway to make a long story short....a mouse chewed thru one of the wires on one of the fuel injectors. I have 5 vehicles, 2 in the attached garage and 3 in the detached garage. Go figure. And after 8 years. So, never say it couldn't happen. Lots of reasons for an engine to run rough.
I agree with several of the other posts. Very unusual for a head gasket to fail that catastrophically with no warning. And those are almost all overheating issues that cause failure.
I agree with several of the other posts. Very unusual for a head gasket to fail that catastrophically with no warning. And those are almost all overheating issues that cause failure.
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03HiYoSilver
Well-known member
Since you have a GenI - have you looked at your Main Harness Coonector?
https://www.fjrforum.com/forum//index.php?s=&showtopic=22734&view=findpost&p=268059
https://www.fjrforum.com/forum//index.php?s=&showtopic=22734&view=findpost&p=268059
teacherman
Member
Mystery solved. We had a bad year for pack rats in Northern Nevada. Ate the wiring on my truck. Bottomline is that the little creatures somehow got into the airbox, damaged the seals and all the debris they "packed" got sucked into the engine. Pistons, rings toast. Got some barn cats from the Humane Society.
SkooterG
Purveyor of Crooked Facts
Wow. Major bummer. At least the mystery of 'why' is solved, but I imagine that is small comfort.
What are you going to do? Replacement engine off ebay?
What are you going to do? Replacement engine off ebay?
03HiYoSilver
Well-known member
Unbelievable! Sorry this had to happen to you.
On my AirHorn, I placed some Chicken Mesh over it to keep the critters out...just in case.
Good Luck with your fix...
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RadioHowie
I Miss Beemerdons!
Skooter, just by serendipity (and the particular threads I'm subscribed to) I have your answer to the above question:
HERE
carlson_mn
Well-known member
Sorry to hear about that. Hope you are able to find a good replacement engine. You won't be the first to have to go through that hassle.
wheatonFJR
...
Sorry about your issue...that sucks.
...checking airbox tonight to see if those critters are trying to stay warm in there.
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dcarver
Well-known member
Freaking rats.
Forest rats.
Piston rats.
Valve rats.
RATS on your bad luck, that just sucks.
Forest rats.
Piston rats.
Valve rats.
RATS on your bad luck, that just sucks.
Hmmm can I ask a silly question...?
What exactly got ingested into the motor? I'd say rats use straw, twigs, dirt (whats on them of the debris), cloth, etc, for building nests. Since the butterflies are closed, the debris only got ingested as you tried to start it this one time (correct?). So spinning your motor a few revolutions ate some of this stuff and destroyed your rings? Ya sure? Just sayin, if you ingested a bunch of dirt Id say over time running it like this and still ingesting dirt would do your rings in, but not just spinning it a little to start it.
I may be dummerer than bust, but Im just….puzzled here. I can understand why the motor didnt start, not the low compression. Again as I mentioned in a previous post on this thread, dcarvers with some nasty damage leaking coolant into the motor still starts. Go figure.
Getting more interesting. :huh:
Sorry about all this, hope it works out well. Gonna keep the 06 ya bought? That guy has a nice 07 fer sale.
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RadioHowie
I Miss Beemerdons!
I think Some are missing the point of my earlier post, so here's a cut'n'paste from a reply teacherman made in another thread:
Whatcha wanna bet there's NOTHING wrong with his '03, other than some trashed-up throttle bodies?
It appears to ME that teacherman has purchased an '06 to replace his rat-infested '03. Granted, it's an assumption on MY part, but he clearly states in a post dated December 28th at 1:26pm that he's purchased another FJR. That certainly post-dates his most recent reply to THIS thread, which was 12/28 at 1:20pm.
Whatcha wanna bet there's NOTHING wrong with his '03, other than some trashed-up throttle bodies?
TomInPA
Well-known member
Even with major rat infestations, the air filter is a paper filter surrounded by a fine stainless steel wire mesh. The air intake and throttle bodies are pretty well protected, and the packed filter should have simply prevented a start by blocking air. I guess the rats must have actually eaten through the filter and mesh allowing the crap to be released into the airbox plenum. Still, I would suspect more problems in the heads from debris being ingested into the valve train, than in the cylinders and lower engine area. If the debris is keeping valves from fully closing (think carbon deposits), this would account for compression issues alone.
