05 Dies at 143,331

[blufjr]

Also, tight valves could do the same thing... were they adjusted recently? Or the Cam Chain could have jumped a tooth or 2.

Valves were done at 129K (Jan.2012). Mech. didn't check the cam chain or he didn't mention it. If the timing was off, it wouldn't effect the compression would it? I could see it not starting.

 

[03HiYoSilver]

Also, tight valves could do the same thing... were they adjusted recently? Or the Cam Chain could have jumped a tooth or 2.

Valves were done at 129K (Jan.2012). Mech. didn't check the cam chain or he didn't mention it. If the timing was off,

it wouldn't effect the compression would it? I could see it not staring.

Yes, it would Start (and they have) even with 1-2 teeth off.

Just something else less distasterous or expensive to consider for your comprehensive evaluation. Your cylinder compression numbers were just too evenly too low and it usually does not happen like this.

 

[ionbeam]

...After the first reading, a leak-down test was performed and checked with two different gauges...

The great thing about a leak-down test is that you can pull the oil fill plug and listen. If the engine is leaking past the rings you can hear it hissing through the oil filler. If it is leaking past the intake valves you can hear it hissing in the intake runners. If it is leaking past the exhaust valves you can hear it hissing in the exhaust headers. Where did your mechanic hear the air leaking?

Valve timing can indeed cause low compression but it should be uniform for all the cylinders. Early valve closure will prevent the cylinders from filling completely. Late valve closure can cause intake/exhaust overlap to bleed off some of the compression. But, it would be uniform for all cylinders.

A leak-down test would show something like Cyl 1 92%; Cyl 2 90%; Cyl 3 91%; Cyl 4 89% which is how much your cylinders are leaking down from a perfect 100% seal with no leakage. For non racing cars 85% is a lower limit. Motorcycles are usually tighter than this and range from 90% sealing or better. Again, cold engines don't seal as well as a hot engine, it is the same for compression testing a cold engine. A cold engine could have a compression reading in the 100-110 psi range and be normal.

Compression testing reads in PSI per cylinder. If you mechanic did not give you readings as a % of leak-down then he did not do a leak-down test.

Edit: I see that 03HiYo posted similar info while I was typing.

 

[blufjr]

Compression testing reads in PSI per cylinder. If you mechanic did not give you readings as a % of leak-down then he did not do a leak-down test.

I went and got the invoice: Comp: 1-50 psi, 2-100 psi, 3-75 psi, 4-55 psi and "Leak down past valves 30%". (leak down wasn't given per cylinder).

 

[03HiYoSilver]

Here are the Compression Numbers from the Manual:

Compression pressure (at sea

level)

Minimum

1,390 kPa (13.9 kg/cm2, 198 psi)

Standard

1,600 kPa (16.0 kg/cm2, 228 psi)

Maximum

1,790 kPa (17.9 kg/cm2, 255 psi)

Hope it works out to something more simples and less expensive for you.

 

[blufjr]

Here are the Compression Numbers from the Manual:

Compression pressure (at sea

level)

Minimum

1,390 kPa (13.9 kg/cm2, 198 psi)

Standard

1,600 kPa (16.0 kg/cm2, 228 psi)

Maximum

1,790 kPa (17.9 kg/cm2, 255 psi)

Hope it works out to something more simples and less expensive for you.

And that is why it won't start. Without tearing it down, it is going to be a mystery. Economically it is cheaper and faster to move the plastic over to the 36,000 mile FJR.

Thanks for the discussion. Good stuff.

 

[03HiYoSilver]

I would check the Cam Chain for proper alignment... it could just be that since the Mech did not seem to Check it the last time...

One or Two teeth Off could just be your problem!

 

[Bustanut joker]

Right on Alan.. TEQUESTAfjr a member on the forum across the road, had the same issue. Dealer did a compression check and informed him his engine was toast.

Oil was added per someones suggestion, an by golly if it didn't fix the problem.

I'd go that route before I went to anymore trouble.

Did oil "fix" the problem...or help correctly diagnose the problem?

I assume that the RingFree helped fix the problem.

...but that is just from reading Alan's post above yours...I am shamefully but a novice regarding things mechanical...

Not sure Mark. The only posts thusfar indicate just an oil change....

 

[jeremyr62]

Here are the Compression Numbers from the Manual:

Compression pressure (at sea

level)

Minimum

1,390 kPa (13.9 kg/cm2, 198 psi)

Standard

1,600 kPa (16.0 kg/cm2, 228 psi)

Maximum

1,790 kPa (17.9 kg/cm2, 255 psi)

Hope it works out to something more simples and less expensive for you.

Has anyone ever actually seen numbers towards the quoted top limit? I did my bike and they were in the range 170-210 psi. Engine was stone cold, wide open throttle. Would expect maybe a 10% increase if I did it hot, this is just a guess though. Engine had been dynoed and was OK in the power dept.

 

[BobbyBlue]

Sorry to hear another 05 ready to put down, or at least pasture, Condolences Blue. Glad to hear ya got backup !

Blessings,

Bobby

 

[dcarver]

Here are the Compression Numbers from the Manual:

Compression pressure (at sea

level)

Minimum

1,390 kPa (13.9 kg/cm2, 198 psi)

Standard

1,600 kPa (16.0 kg/cm2, 228 psi)

Maximum

1,790 kPa (17.9 kg/cm2, 255 psi)

Hope it works out to something more simples and less expensive for you.

Has anyone ever actually seen numbers towards the quoted top limit? I did my bike and they were in the range 170-210 psi. Engine was stone cold, wide open throttle. Would expect maybe a 10% increase if I did it hot, this is just a guess though. Engine had been dynoed and was OK in the power dept.

My Ebay 2006 engine, after sitting for 7 months...

Cyl1 Cyl2 Cyl3 Cyl4 230 225 225 220

 

[yamafitter]

I went and got the invoice: Comp: 1-50 psi, 2-100 psi, 3-75 psi, 4-55 psi and "Leak down past valves 30%". (leak down wasn't given per cylinder).

Readings this low indicate serious issues but I am confused with the quoted leak down value a little bit. I'm thinking with compression values that low that there are stuck or broken piston rings. I would think that if the problem was with the valves and with compression readings this low the leak down test would have been much worse than 30%.

 

[jeremyr62]

Here are the Compression Numbers from the Manual:

Compression pressure (at sea

level)

Minimum

1,390 kPa (13.9 kg/cm2, 198 psi)

Standard

1,600 kPa (16.0 kg/cm2, 228 psi)

Maximum

1,790 kPa (17.9 kg/cm2, 255 psi)

Hope it works out to something more simples and less expensive for you.

Has anyone ever actually seen numbers towards the quoted top limit? I did my bike and they were in the range 170-210 psi. Engine was stone cold, wide open throttle. Would expect maybe a 10% increase if I did it hot, this is just a guess though. Engine had been dynoed and was OK in the power dept.

My Ebay 2006 engine, after sitting for 7 months...

Cyl1 Cyl2 Cyl3 Cyl4 230 225 225 220

Colour me jealous then.

 

[08FJR4ME]

Could it be that the Valves are Not Seating Properly... this would give bad numbers as well.

That could be? I must confess that I am agressive and use a lot of high revs and compression breaking, which usually reduces the junk and cause for bad seating but wouldn't you need to remove the head to fully analysis that?

OH ****,

I am doomed!

Dave