Low compression. Head gasket failure?

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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:

I picked up a 06 AE yesterday with 5900 miles on it in pristine shape for 7900. I searched for several weeks. Not a lot of them were out there in CA. Sell the bike as stated above.
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?
+1 , Gunny and fuzzy balls :eek:

 
Geez, any thread about engine failures and all the Gen 1 motorheads chime in. They're bloody experts at

diagnosing jacked-up powerplant problems. Hell, half of 'em are on their second engine. Trying to coax a few more miles

out of those relics.

I'm so glad that Yamaha had things sorted out & dialed-in ....beginning in 2006.

(Is this an incendiary post? 'Cause that's not what I was aiming for.... MEM had made some observations and I just thought I'd share.

...........Jus' tryin' to contribute.)

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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.
That's my vote. Don't see how the rings are affected. But how to clear the valves? Might still have to pull the head. Sounds like a good project engine.

 
I am just guessing here but I find it hard to believe the engine has real damage. I'd take off the throttle body and suck the runners out clean with a shop vac. Then pull the plugs and suck out the cylinders while turning it over. Then squirt oil in the cylinders to restore the compression which was lost due to over fueling the engine when it wouldn't start and couldn't get any air. Reassemble and your fine.

There, I fixed it.

teacherman, wanna sell that thing?

 
I am just guessing here but I find it hard to believe the engine has real damage. I'd take off the throttle body and suck the runners out clean with a shop vac. Then pull the plugs and suck out the cylinders while turning it over. Then squirt oil in the cylinders to restore the compression which was lost due to over fueling the engine when it wouldn't start and couldn't get any air. Reassemble and your fine.

There, I fixed it.

teacherman, wanna sell that thing?
I'm with you, except I don't think I'd pull the throttle bodies. A shop vac on them with the throttle plates open would probably work fine. It's time to have somebody that knows what they are doing diagnose that thing. If not, somebody is going to get a heck of a deal on it.

5 years ago I bought a Nissan Altima that wouldn't pass NY State Emission Inspection. It had a misfire in it. The owner replaced all the ignition components, installed new injectors, and a new fuel pump. When he gave up I bought it for under $500.00. The EGR valve return spring was weak. It opened too much causing a miss. That guy lost a good car over not wanting to pay to get it diagnosed.

2 years ago I bought a 1998 Subaru Forester for $300.00, It was a no start, and was diagnosed as needing an engine. The cam timing was off 2 teeth, and if cam/crank signals are not synced you won't get spark. I put a new timing belt in it, and did a bunch of other little stuff to get it back in shape.

I just sold the Nissan this year, and my wife drives that Subaru about 700 miles/wk. They've been great cars, and I got them for a song, only because of situations EXACTLY like this.

Teacherman, please stop trying to diagnose this bike with the Diagnostic Dartboard and take it to a reputable shop.

Joe

 
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