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Discussion Starter #1
Hello-
I've been messing around w/ a 1976 Jag 3000 w/ the spirit 340 f/a engine. I drove it for about 20 min around the lawn then started to bog. I restarted it after a few minutes and limped back to the garage. Tried to restart again and pow! what looked like gas blew out of one side of the cylinder after closer inspection the head gasket blew out there. What would cause that? Should I just replace the blown head gasket or does this typically happen due to some other problem? The engine had good compression on both cylinders before this, in addition good spark and started 1st pull and ran strong. I appreciate any info! (Also - how many lbs. or torque on the head bolts?

-Adam
 

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Pull the head off and look and see. It is 30+ years old and almost every freeair has got pretty hot atleast once :slick: if the cylinders look ok to you put a head gasket and go.
 

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use tinfoil to give her more power as a head gasket.[/b]
Hey I took the heads off and replaced the headgasket (used a little RTV on gasket like manual says too). I torqued it to 29lbs (manual says between 22-30) and I followed the rec. pattern of tightening. After one pull the new head gasket blew out!! I noticed A LOT of gas literally pouring out of the exhaust can. I took off the exhaust and emptied it of fuel then pulled on the recoil and watched LOTS of gas come pouring out of the ehaust manifold. Does anyone know what is causing this? Thank you for the use of this site.
-Adam
 

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hi, i too am still messing with a 77 jag 340. F/A motors are wierd, mine has 2 bad crank seals after sitting for 1 year, and it has low compression even after i put pistons in it. Well anyways i live in WNY, and was wondering if u were interested in selling the sled. I love old cats, and my 1974 Cheetah 340 gets more miles than my XLT600. well anyways maybe we can work something out. If u need parts i might have some
 

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hi, i too am still messing with a 77 jag 340. F/A motors are wierd, mine has 2 bad crank seals after sitting for 1 year, and it has low compression even after i put pistons in it. Well anyways i live in WNY, and was wondering if u were interested in selling the sled. I love old cats, and my 1974 Cheetah 340 gets more miles than my XLT600. well anyways maybe we can work something out. If u need parts i might have some[/b]
Hey-
I would possibly sell the sled - I was hoping to spend a little time on the trails with it though! I don't have a heated garage so I'm not sure how much work I'll actually end up doing. If you want to buy it come take a look e-mail me at [email protected] and we can set something up. The sled drives nice and looks nice - not show quality but brand new seat cover, windshield and nice intact hood. All lights/electrical work well and the track is decent. (Just the damn motor!!) Any ideas why it filled up w/ gas? Is there a drain lpug on the bottom?
 

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hoe much you looking to get for the sled. IF the crank case is filling up with fuel, it is possible a crank seal issue but not sure. if you can, look at where your clutch is and see if you seal poped out. When i took my sled apart to chack the seals, the crank case was full of fuel so its a possibility.
 

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hoe much you looking to get for the sled. IF the crank case is filling up with fuel, it is possible a crank seal issue but not sure. if you can, look at where your clutch is and see if you seal poped out. When i took my sled apart to chack the seals, the crank case was full of fuel so its a possibility.[/b]
The seal is ok on the PTO side. About the $$ I'd take $350 for it or $500 if I replace all the seals and gaskets.
 
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