Rebuild or...

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josh
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Rebuild or...

Post by josh » Sat 26. Feb 2011, 23:30

Hi, my name is Josh, and I own a 1964 Lincoln.
I did something really stupid a few months ago and, while adjusting (monkeying around with) my freshly rebuilt carb, I bumped the throttle a bit too hard it would seem and heard a terrible noise. I found that I had bent five of my pushrods and so the car sat for a couple of months while I kicked myself, ordered new pushrods and gaskets, thought of whether or not I should take the heads off and inspect further, thinking that it MAY be a waste of money to do so, thinking that I didn't have money to waste, and then finally getting back out to my car.

I didn't take the heads off...'cause...well, I don't have a convincing argument for that, really, but let's just say I was afraid of bad news. I replaced the pushrods and put everything back together. A friend turned the key, the car started up, and sounded like utter crap. I told him to immediately shut it off. During the approximately 6 seconds that it was running, I thought that I had discerned that the number 6 piston wasn't doing anything. The engine shook, and it just sounded bad from that area.

I am assuming that I will require a complete rebuild. I'll know for sure when I get another free afternoon and can take the heads off and really look around. In the mean time...

My questions are:
Since I am completely broke, what is the CHEAPEST one can rebuild one of these engines for? Parts, etc. I'll have to find a machine shop here that is competent and hopefully will be reasonable, but an estimate from those experienced would be nice.

If I can't afford that, what would be the odds of finding a solid running or rebuilt MEL in the Western Arkansas area for cheapish?

And finally, which would be the best option? Rebuilding the engine as cheaply as possible, or finding a temporary donor to use while a save for a proper rebuild?

Obviously I'm in a hurry to get it back on the road. It is my dream car, after all. Unfortunately, finances have been extremely tough for the last two years, otherwise there wouldn't be a question about what to do. Hopefully I can get something of a tax return this year and be able to do SOMETHING.

Thanks,
Josh

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Re: Rebuild or...

Post by vanscooter » Sun 27. Feb 2011, 05:51

This is a tough one Josh. There is no such thing as a budget rebuild with one of these motors. Figure out what is wrong and fix it for now. Yank the valve covers off and have a look for simple stuff like broken rocker arm, maybe a rocker is worn and slapping, did you hit a valve when the pushrods bent ? The pushrods are meant to be the weak link and bend first in the case of a mess up.
Let us know as you get into it.

Good luck, vanscooter

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Theo
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Re: Rebuild or...

Post by Theo » Sun 27. Feb 2011, 09:09

Like vanscooter said. This a tough one. Temporarily flooring the gas pedal does not necessarily lead into bent push rods IMO. I second vanscooter's advise to inspect the rockers and all else below the covers. Taking off the cylinder heads might be an other option. Double checking things is mandatory when dealing w. engines.
You said you had a freshly rebuilt carb. Is the engine freshly rebuilt too? Are you running a stock cam? Who was the last one who fiddled w. the engine? Any modifications? Can the last owner be asked for further information? Stock length push rods? Did the rocker arms slip off the valve tip?
Did the pistons hit the valves? Find out why, if yes. Possible reasons are other than stock dialed in camshaft at the sprocket.
Too long push rods resulting in excessive lifter pre load. Excessive lifter pre-load (can) result into reduced piston to valve clearance on TDC while they pump up under speed. Coil bind problems ? Sticking valves (don't think this is the problem on your particular engine as it is almost impossible to encounter 5 sticking valves all at the same time).
Questions and questions. Think it over and work your way step by step from the valve train down to the pistons. Also keep in mind that block and cylinder heads that have been milled numerous times change the engines clearance specs on critical components such as push rods, coil height and head room, lifter pre load, valve to piston clearance etc.
You're welcome to ask for more assistance. There are no stupid questions and no questions that you can ask too often. Don't skip things in a hurry. It would only lead to more money and time wasted. Unless you can't find a good running and reasonably prized used engine, make sure to work precisely and w. quality parts.
Also, don't buy everything any parts vendor rep is telling you. There are virtually no reliable sources for MEL consumers. If there are parts and specs. in question, please ask and double check in this forum. This counts especially for pistons. The Ladies and Gentlemen in this forum will be pleased to pass over their experience and expertise to you. You only need to be a little patient as traffic can be a little slow here.
Let us know what you find out.
Good luck w. your project.
Best regards
Theo
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josh
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Re: Rebuild or...

Post by josh » Sun 27. Feb 2011, 16:22

Thank you very much for the responses.

Concerning the valves and rocker; I did have the rockers off in order to replace the pushrods and they looked fine. Also, the valve stems (which was all I could see, of course) appeared straight and of equal height. My thought was that, perhaps, while it was sitting and waiting for the carb to be rebuilt and put back together, that a few of the lifters may have seized causing the pushrod failure. Perhaps I may have spun a bearing the second go-round.

Obviously, I have no idea, this is all just speculation at this point. Right now I'm just kicking myself for not having joined this forum and begun asking questions earlier.

I will keep you posted, and I'm sure more questions will be forthcoming, though it may be a while between updates.

Thanks again,
josh

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Theo
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Re: Rebuild or...

Post by Theo » Sun 27. Feb 2011, 16:31

I don't think the lifters were stuck. That would be extremely unusual.
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Re: Rebuild or...

Post by vanscooter » Sun 27. Feb 2011, 16:33

If it sat for a while waiting for the carb the lifters might have bled down. They would be loud on the initial start, a clacking sound until the oil would pump up, hopefully. If they did bleed down it would be in a safe mode, not enough lift to open and close fully. Would run bad like a miss, maybe even a backfire. Pull a plug and look for something odd= water, oil, aluminum speckles. Did the timing chain jump or slack off ? I wouldn't pull a head yet. Do some research here on the forum. Start small. Don't overthink it yet. Keep us posted.

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Re: Rebuild or...

Post by Theo » Sun 27. Feb 2011, 16:38

vanscooter wrote:....... Pull a plug and look for something odd= water, oil, aluminum speckles. Did the timing chain jump or slack off ? I wouldn't pull a head yet. Do some research here on the forum. Start small. Don't overthink it yet. Keep us posted.
Jep, I'm with you. Pulling plugs is what comes first. I forgot to mention that.
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430 6V
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Re: Rebuild or...

Post by 430 6V » Sun 27. Feb 2011, 17:40

Before any teardown, and being on a budget, I would buy, borrow or rent a compression tester to check the engines condition. If valves got bent it should show.
Leakdown tester would be better but barring that the compression test line can be adapted to a compressed air source so any cylinder leaks can be found. Remove rocker shafts for the second one

In addition to looking for lifter issues check for broken valve springs.

IMO

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Re: Rebuild or...

Post by josh » Mon 28. Feb 2011, 14:42

Excellent. These are all very good ideas. Thanks you very much. I'll keep you posted on my progress.

-josh

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Re: Rebuild or...

Post by keithol » Tue 1. Mar 2011, 17:36

I think the leakdown test is an excellent idea ,even with makeshift equipment. I have made adapters from old hollowed out spark plugs welded to fittings to hook up to shop air. Just listen to where the leaks are, some leakage past the rings is normal , past the valves is not. My guess would be ,the timing chain jumped enough to bend the pushrods and a valve or two . If this engine has never been torn down before ,it would have a camshaft sprocket with nylon teeth on an aluminum hub. It kept chain noise to a minimum, but the nylon would shrink ,crack , and flake off, leaving the chain so loose it would slip. Nearly all the engines back in the sixtys had them. If the chain has jumped ,your ignition timing will also be off, you can check static timing by bringing the number one cylinder up on compression. With the timing marks lined up,the points should be at the moment of opening, with the rotor pointed to number one terminal in the distributor cap. If you want to be accurate for the opening instant ,use an ohmmeter. The other thing you may want do is turn the engine back and forth ( with a socket on the end of the crankshaft) while observing distributor shaft rotation. I would be willing to bet that you will be able to turn the engine quite a ways without moving the distributor shaft. At any rate, if it is a timing chain and /or bent valves you should be able to patch it up until better times, without breaking the bank. Good luck !
Last edited by keithol on Tue 1. Mar 2011, 19:06, edited 1 time in total.

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