Two dead cylinders (1 Viewer)

[runningdaddy]

That's the diagnosis from the mechanic on my 82 FJ40, original 2F. Mileage over 160k, that's when the odometer died. And low compression on two others.
Rebuild for $$ or engine swap?
I'm in Hawaii ( I'm sure I'll get ZERO pity now) and machining is expensive.
I'm concerned the cost of engine swapping will be just as expensive or more after changing out electrical and exhaust components.
Any input would be appreciated.

 

[78fj40mg]

No guaranty with a swap you are better off rebuilding.

 

[65swb45]

If they are two adjacent cylinders, it could just be a head gasket.

Mark A.

 

[Solace in Solitude]

X2^^ please list compression by cylinder

 

[runningdaddy]

I don't have the numbers for compression by cylinder. 1 and 2 were shot, so I could see faulty head gasket. I think 3 and 4 were lower compression.

 

[runningdaddy]

I should also add that the engine will start and idle, sometimes with choke assistance, I can drive around the block a few times and then I get a sluggish, dead gas pedal. The engine will stall and die. If it does start again, it is the roughest running engine I've ever heard.

 

[snaggletto]

A basic rebuild would be best in my opinion if that is what is needed. Before that though, I would replace plugs, plug wires and distributor cap, and check timing. See about a compression test and leakddown test to see what the problem really is, before anything else tries to be fixed. My 2F is in pitiful shape but still runs reliably.

 

[winnie]

I agree with what the others have said ... re-do the compression test(s) so you have the numbers to compare ... is the mechanic a cruiser-head ... cheaper replacing a head gasket than doing a rebuild (swap wouldn't be my choice if it comes down to that kind of decision) ... if its a head gasket use Toyota ... I have one low cylinder in my truck ... I'm running it till it stops (they aren't race cars to begin with) ... good luck ...

 

[65swb45]

I don't have the numbers for compression by cylinder. 1 and 2 were shot, so I could see faulty head gasket. I think 3 and 4 were lower compression.

This is the key. " lower" by who's standards?

The miser in me says run 'em 'til they won't.

The cruiserhead that I have been for the last thirty years has witnessed too many crapshoot rebuilds by good machine shops working with 'quality' parts to go down that road until you have to.

Since you posted here for advise, you're pretty much 'on the hook' to post compression numbers now.

No guarantees, but I have personally witnessed these guys and gals talk a guy with a spun bearing thru a polish and replacement. New friendships were made too.

Best

Mark A.

 

[CruiserClay]

This is the key. " lower" by who's standards?

^Exactly. The compression #'s are crucial to have. You can't really pinpoint the problem(s) without knowing what kind of compression you have throughout the various cylinders. An engine will run with 3 things: Fuel, Spark, Compression. With only those 3 things, it may not run well, but it'll run. Then you can figure out what's wrong and remedy that specific issue. Anyway, hope you get things sorted out and get back on the road.

 

[honk]

An engine will run with 3 things: Fuel, Spark, Compression.

Needs some air, too.

 

[CruiserClay]

Needs some air, too.

Absolutely true, although I was counting "fuel" as the mixture of air and, in this case, gasoline.

 

[runningdaddy]

The compression numbers from 1 to 6 are 0/0/115/90/140/120

 

[Tools R Us]

When was the last valve adjustment? Have seen a few where it was so far out (tight) that it caused dead holes, adjusting them brought it back into the livable range.

 

[honk]

The compression numbers from 1 to 6 are 0/0/115/90/140/120

That's not good.

If you can still get it running look into the radiator for any bubbling and is your oil cap covered with a milky/oily almost white colored goo?

It might be worthwhile to adjust the valves but it really sounds like your engine needs to be torn down to find the problem(s). If you can pull off the cylinder head you'll likely find issues. If you do that be sure to post copious photos of what's in there so these guys can give good advice and hopefully save you some money.

 

[SuperBuickGuy]

The compression numbers from 1 to 6 are 0/0/115/90/140/120

It's possibly a cracked head between 1 and 2 exhaust ports. Bet your exhaust gasket was blown for awhile.

You should look for a replacement motor, given your proximity to the US mainland and Japan, I bet a JDM motor from Japan would be pretty reasonable. If you were here in the US, the world really is your oyster from diesels, to LS Chevy motors, to whatever flavor you want to put in.

and to be clear, I'm actually less concerned about 1 and 2 (which could simply be a blown gasket between the two cylinders) than I am about #4 - that one's probably a burned valve which means you're getting a new valve and valve job (read, not cheap). #4 might have been caused by a cracked manifold or leaking center gasket... so beside the head rebuild, you're looking at a new exhaust manifold as well... which probably adds up to more than a JDM replacement and not putting more money into a motor that will last 40k-90k before it needs the rest of the motor rebuilt.

 

[runningdaddy]

I was doing pretty good until SuperBuickGuy's post on cracked head. That just scared me.
I tinkered with the valves with a buddy about a month ago while trying to trouble shoot the loss of power after warming up.
Right now, I need to spend more time with family, which means more $$$ for my mechanic. I'll keep you posted on the repairs, but I'm giving the green light to take the head off and see what he finds tomorrow.
Thanks for the suggestions. Especially to SBG and the engines from Japan; it got me to find some great engine possibilities on the West Coast.
Mahalo!!

 

[edwjmcgrath]

Pulling the head makes sense. All the bad stuff could just be a head gasket OR it could be cracked head or piston/block issues.
You'll never know until you pull the head..

 

[runningdaddy]

Leak down test confirmed rings were shot. Expensive, but if they lasted 33 years, it's worth the investment to drive my cruiser for another 33 years.
Waiting to get the engine back from the machine shop and back under the hood.

 

[DougAustinTx]

"Rings were shot" would explain some of the low numbers on the cylinder pressures, but I have never seen a piston with rings so "shot" that two adjacent cylinders were reading zero (0). What was the condition of the head gasket between cylinders 1 and 2?