What's next - 2F issues!

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MD11Fr8Dog

CM09 Eight Ball winner
Joined
Apr 6, 2002
Threads
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534
Location
Southern Pines, NC
In starting to get my FJ40 ready to haul out to Cruise Moab, I did a Combustion Leak check (Lisle blue water thingy) and found I have leaks in #3 and #4. I suspect a bad head gasket between/near #3 and #4, but before I pull the head and replace it, any other thoughts? I did a quick compression check and got 155, 150, 138, 138, 148, 155. The only real symptom I had was occasionally I'd overflow the overflow bottle after shutdown - it would sputter and spit!

Here are what the plugs looked like when I pulled them:

IMG_1064.jpg


History of the engine: Its the original 2F in my 75 FJ40. I seized it back in Sept '01 and then rebuilt it - new bearings, new crankshaft from Mark Whatley, milled head, new valves, stems, rockers, etc. The cylinders were okay and so I only had them honed, but I added new pistons. I used the rebuild kit from PacLift. Most of that reassembly was done in late '01/early '02. The motor, however, was not ever filled with fluids or turned over until about Jan/Feb of last year! The engine probably has about 400-500 miles on it since the rebuild.

I'm hoping/thinking that the head gasket probably had just dried out and gotten compromised. Any other thoughts and/or anything else to check before I pull the head?

Thanks!:beer:
 
You might want to try a wet compression test. squirt a small amount of oil in the cyl then run the same compression test you have there. if you see a dramatic increase in pressures you may want to remeasure or just bore the cyl's. I 'rebult' a gett-er-by engine and just honed the cyls, and mine smokes like a factory. it could be valve giudes, but I'm thinking the honing only was not such a hot idea. Good luck!
 
Hey Sean! I was thinking about you a couple of weeks ago while I was at Katemcy. It's been a while. 2005 I think.

Anyways, I think it's more than a coincidence that those two middle cylinders share the same compression. That said, I'd also be picking up a really good straight edge to check the block deck for a 'dip' in the middle. Check the head too.

If you're not loosing a lot of water, you might want to run it a bit longer, just because you should have a better 'carbon trail' on the head and block when you pull the head. Maybe another 500 miles.

Best

Mark A.
 
Hey Sean! I was thinking about you a couple of weeks ago while I was at Katemcy. It's been a while. 2005 I think.

Anyways, I think it's more than a coincidence that those two middle cylinders share the same compression. That said, I'd also be picking up a really good straight edge to check the block deck for a 'dip' in the middle. Check the head too.

If you're not loosing a lot of water, you might want to run it a bit longer, just because you should have a better 'carbon trail' on the head and block when you pull the head. Maybe another 500 miles.

Best

Mark A.

Yep, '05 Katemcy. I upgraded to Capt and we moved from CO to NC a yr later, so I have been "out of touch" for a while! IIRC, you ripped your canvas top on that tight twisty trail at Katemcy that year? Iron seat award too, right?

I was thinking the same thing as you are suggesting about the "dip", it struck me as I was writing out each compression test result. Talking with some folks on LCML and a few Facebook contacts, I think I'm going to just retorque the head bolts for now. Its not a bad leak, at least not yet. I can't smell it in the radiator and I have no funky/foamy/oily water. I'll take spare head gaskets to Moab and pull the head there if necessary! I'll be picking up some stuff at the local TQL parts desk tomorrow, so I'll order a couple OEM head gaskets while I'm there!

Thanks!

BTW - you going to CM09? That's my long trip this year, maybe in a couple years I'll make it out to the left coast!
 
Update:

At the suggestion of the someone on the LCML, I decided to retorque the head bolts and see where that got me. So, I pulled everything off and then noticed/remembered that the middle bolt on the passenger side is blocked by the rocker assembly. I retorqued all of the other bolts and almost blew off that middle bolt! Glad I didn't. I pulled the rocker assembly and retorqued that bolt - required almost a full qtr turn to get to 90 ftlb. Buttoned it all back up, and did another compression check and combustion leak check. No combustion leak detected, using my Lisle tester, and the compression numbers all improved - 157, 155, 146, 148, 155, 155 (1 - 6).

All is good now! :D
 
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