2F Compression Costa Rican Fj40 (1 Viewer)

[cooksflips]

1976 Fj40 purchased in 2003 from someone claiming to have purchased from an individual who imported it from Costa Rica. This wold make sense as it is worn out in many a places. I have been driving it hard sense 2003. Did a compression test today.
Cylinders are as..
1-100
2-110
3-100
4-85
5-90
6- ???? got compression to 90 but would not hold. Fell flat after 4 seconds.

Spark plug on cylinder 4 was very oily and black, number 5 and 6 even worse.

Is a valve job even worth it or am I need of a total rebuild ???

FYI When I floor it while stuck there is alot of smoak ...... i think she is toast.

I wanted to pull the head, mill it, grind the cam and valve job it.

What yall think ????

 

[LandCrusher'70]

If it were me, I’d pull the head. Get your eye on the cylinders and head gasket. If the cylinders look “good” and the HG looks “bad”, get the head worked, throw on a new HG, and run with it.

 

[greenbeasty]

I agree with @LandCrusher'70 , if it's not a substantial improvement in performance, you were gonna spend that money anyway. Tear it back down and do the whole thing. I've got a good machinist in Asheville.

 

[Dizzy]

The oil could be valve stem seals. The low compression could be because the engine can't do a complete intake stroke, or that it can't hold the intake charge. Before a compression test, valve lash should be addressed.

 

[Michael Hanson]

Hi, In Costa Rica cruisers are worked hard,some every day hauling everything. Personally I’d rebuild the engine, more than likely time. Mike

 

[cooksflips]

Thanks for everyone that commented hear. I filled cylinder number 6 with oil today and did another compression test and got a reading of 220 so that tells me the rings are bad ....??? I went ahead and buttoned everything back up and am going to drive it though the summer and tear into this winter. Ill post again when i get into it.
- John