It ran when I bought it, head gasket failures?

[Anonymous]

Hi, I'm a new guy in New Jersey. Like some one else recently posted, wit's end is coming up fast. I bought a 69 Falcon wagon in Kansas and drove it back to nj. Most of the trip was with a flooding Ford carb and a head gasket blown between 5 and 6 cylenders. It ran fine when I left Kansas. When I replaced the head gasket, it looked like the gasket was about to fail between cyl 3 and 4 also. New gasket in place and now my problems are in the carb, flooding out at idle. New rebuilt kit in the rebuilt carb and I was still having float sticking and flooding. Now it's popping through the carb and not running at all. Compression test shows 140 pounds compression in all cylinders except 3 & 4 (60 lb and 110 ) with all plugs out, 90 lbs each checking one at a time. I figure this means head gasket is failing. I will be pulling the head again. This time I will send out the head to have it checked for level, but what about the block. I don't have facilities available to pull the engine, and if it's the block, they can't plane it with the pistons still in it can they? The rebuild was a backyard special, and it's going to kill me to rebuild the rebuilt engine. I have 2 V-8's available me and would be cheaper to just swap them. But the 6 might be fun to play with. I need the cheapest, easiest way to figure this out. Also, I just replaced the ford carb with a holley. I am in the process of starting at ground zero, checkin initial timing, etc. But it's doing exactly what it did when it first wouldn't run. It wants to start, then pops back out the carb. Tomorrow is another day. What do we think? thanks Johnny

 

[CZLN6]

Howdy Johnny:

Welcome to the Adventure. Keep it straight!

You are wise to pull the head and have it checked for several issues. The variances in cylinder pressure may be due to a blown gasket, burned valves, bad seats, cracked head, or other problems. This head will not have hard valve seats. You didn't say how many miles are on the engine. It would also be interesting to know what '69 head casting your engine has. Look on top of the intake manifold behinded the carb. You will see a series of numbers that should look something like this, C9DE 6090 K. The "C9" stands for the year 1969. It's the last letter(s) that will tell the most.

A '69 200 would have had a steel shim head gasket from the factory. If you replaced it with a thicker aftermarket composite head gasket, that would account for the low cylinder pressure and lower compression/performance, unless you machined the head to compensate for the difference in gasket thickness. That would not account for the variances from cylinder to cylinder. That is a problem.

If the solution to this head requires complete disassembly, consider a complete valve job which should include a three angle valve job, milling to level and to compensate for an aftermarket composite head gasket, new valve stem seals, and hardened seat inserts if you expect to put alot of miles on this engine.

The '69 Carter YF one barrel carb is fairly easy to rebuild and fairly durable, but they do wear out. Check the throttle shaft for tightness, make sure the parts fit togather well and are not warped. If you find any of these problems, it might be easier and cheaper to get a rebuilt- but, go through it too, before installing.

Which Holley are you now using?

Be particularly careful on reassembly that the needle valve is properly aligned with the seat. Make sure that there is no float or fulcrum interference with the top gasket. Make sure that everything is thoroughly cleaned out and well filtered.

Check the distributor vacuum advance line to the carb, and make sure the vacuum advance cannister is functioning. Be sure to eliminate any vacuum leaks.

Good luck and enjoy the journey.

Adios, David

 

[mugsy]

A couple of things to do.

First re-do the compression check "dry" but then add a teaspoon of oil to each cylinder and re-check. The if the pressure increases it most likely means the rings are shot/bad/worn.

After you take the head off buy a machinist straight edge and feeler gauges. Do not use a ruler or some other straight edge, buy the real thing!!! Then you use the ruler and feeler gauge to see if/how bad the warpage is on the block surface. There is a spec in the Shop Manual. I am not a machinist but did this on my recent rebuild and when I did take the block to a machinist his numbers agreed with mine. So it is possible for a total hack (me) to do it right. So I am sure you can too. Anyway, this will tell you if you need to true or level the block face. Don't spend money (and time) if you don't need to, but you do need ot find out what is going on.

The composite head gaskets are about 0.020 or in that range thicker than the OEM gasket. Machine off that amount at least from the head.

Then do the rest of what was recommended in the previous post.

Tanx,
Mugsy

 

[Anonymous]

Things can change a lot in a day. I have brand new health issue that is going to keep me off my feet for weeks. I may just put the beast up on e-bay as it sits. Check by Friday. The machinist rule is an excellent idea. It should give me a clue. As for engine / head milage. Rebuilt last month. First failure was at 400 miles between cyl 5 & 6. This time, between cyl 3&4, 200 miles. I put in the same fel pro "no retorque, no sealant" thin steel gasket called for in 2 parts store catalogs. As an old hot rod guy and try anything before fixing it right, I have used two head gaskets more than once to take up some uneven spots in surfaces. Do we still try that these days? The previous owner is no longer talking to me. He rebuilt it. I don't know how hands on that means. Did he send it out or do all the work himself? I can't find out any more. I had planned to work on this every day, weather permiting, untiil I fixed it or complex management taged it for tow. Right now I don't think I have any options. I think I'm just going to take the loss. I may not be driving for a while anyway. If I can try to pull the head again I will. Otherwise, rust free Kansas wagon for sale in NJ. Bring your tow bar! Thanks for the advice.