Rebuilt 2F Engine - cylinder dead??

[dv_fj40]

Just installed and new rebuilt 2F engine and head. Everything was good for the first 82 miles and then – well… let’s just say cylinder one is dead – absolutely no compression and I mean no compression.

I might add, I removed the spark plug and it was coated with oil. And there is the sound of a valve out of adjustment – but we checked the valves twice / adjusted with the engine hot – and the sound stayed.

Any suggestions or recommendations????

Pissed off here in Devore (San Bernardino, California).

Joel
www.desertdrifter.com

 

[Dave E]

Check the valve springs. I broke one once just after a rebuild. It's possible it damaged the valve seal. I'd take it back to the shop though.

Dave

 

[Romer]

Could be the rod bearings were not tight and the bottom cap came off. That would keep the piston from going up and down.

Drain the oil and drop the oil pan. Take the plugs out and have someone turn it by hand if its not obvious. I beleive the Rod Beraing caps need to be torques to 35-55lbs. I had a problem torque mine because ihad them in 180 deg out and the engine would not turn with it torqued. If the same thing happened to you, they may not be torqued properly. That would explain the oil.

Just a guess. Let us know,

Ken

 

[dv_fj40]

Ok... took off the valve cover and notice a push rod adj. screw off as with the push rod sticking out above the rest about 2". I pushed the rod back down and did feel the valve lifter fall back into place. I checked the push rod and it is “true” per the specifications of the 2F engine manual. The adj. screw and rocker arm look fine too.

So with that, I pulled the head off to make sure there was no damage to the valves. All looked fine - or I should say there is no visible damage. (Keep in mind; I am just a weekend mechanic, but an engineer by profession.)

The thing that gets me – because this was off, the valve would be shut?!?!? Right?!?!? So why would I not have compression in that cylinder!?!?!?

Any suggestions?

Time to take some auto classes at the local community college?


Joel

 

[dv_fj40]

Did crank the engine over with out the head. All pistons are functional and there is no scouring/scratching on the cylinder walls. In fact, everything still looks brand new.

 

[FJ40 that green thing]

I just had an engine rebuilt as well and after a couple thousand miles it was burning oil again! So I took it back in and the mechanic did a compression test and several cylinders were way low on compression. We were thinking the gasket broke or cracked head or something but it turned out that the valve stems were leaking oil and the whole head needs to be rebuilt again! Yea, talk about frustrating.. It sounds like you've got a pretty good idea of what is going on though. Good luck

 

[dv_fj40]

Well, just got off the phone with the mechinic about my head on my 2F engine. Was told Intake valve spring 1 and 3 (number represents cylinder) were cracked. The spring on 1 was even missing a piece. Ask how this could happen... many different reasons but from the looks of it - they were worn out. Mechinic is replacing them all.

WHEW...

And why there is oil in the cylinder --- brand new engine. Rings have not "set" yet and with some other things. Usually takes about 100 miles or so. I only have about 35 miles combined.

Learning something new every day.

Joel

 

[dv_fj40]

Clarification - first message thread should have indicated 32 miles and not 82 miles.

Joel