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Engine mystery????

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hpva View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote hpva Quote  Post ReplyReply Direct Link To This Post Topic: Engine mystery????
    Posted: Mar/07/2012 at 6:02pm
Last year I had the engine rebuilt in my 59 American(196 L head).I put about 800 miles on it and decided to rebuild the carburetor since it didn`t idle as smooth as I thought it should. This October     my friend rebuilt the carb and I reinstalled it ,the car ran good for a day.The next day I took it for a drive and it started to buck and sputter I had all I could do to get it back to my garage with a top speed of only 20 mph.After a month of fustration I bought a carburetor on ebay and installed it on the car and as soon as I took it for a test drive I started to have the same problem,bucking stalling and loss of power.Now I`m really confused and last week I bought a remanufactured carb from a place in California they set the choke and all the ajustments so its a bolt on and go.You guessed it after i installed it yesterday I took it for a drive and it idled and drove great for a half mile then started doing the same thing again.Today after some thought I started to think it may be a fuel pump problem but before I check the flow out of the pump I decided to plug the vacuum line that goes from the fuel pump to the vaccum operated wipers.Again I did a test drive and lo and behold the car ran and idled great,I drove it for about half an hour and 5 miles with zero problems.I plan on driving it tomorrow to see if it acts up.Could this be the answer has anyone else ever had a problem like this?Does anyone have a theory or an answer to this?Confused
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Post Options Post Options   Thanks (0) Thanks(0)   Quote farna Quote  Post ReplyReply Direct Link To This Post Posted: Mar/07/2012 at 8:17pm
Sounds like you found the problem. Check the vacuum line from the pump to the wiper motor. If it's rubber just replace it. They get old and don't seal very good. The wiper motor itself could have a leak. You can get it rebuilt for under $100 by Peter Stathes (www.amcrambler.com). Cheaper than converting to electric, and it should be good for another 40-50 years.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote hpva Quote  Post ReplyReply Direct Link To This Post Posted: Mar/11/2012 at 3:13pm
Well the car ran fine for three days,today when I took it out it started bucking again.Every time I  stepped on the gas it it would act as if it was running out of fuel but put it in park and it would idle ok.Could it be a failing fuel pump,the gas tank is clean and it has a new fuel filter also.I`m running out of ideas .
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Post Options Post Options   Thanks (0) Thanks(0)   Quote gtoman_us Quote  Post ReplyReply Direct Link To This Post Posted: Mar/11/2012 at 3:36pm
Sure sounds like a fuel pump.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote farna Quote  Post ReplyReply Direct Link To This Post Posted: Mar/11/2012 at 4:49pm
The wiper leak could have been in the diaphragm of the fuel/vacuum pump. So the pump is the most likely culprit at this point. sometimes one of the diaphragms go, but the other is usually close behind it. 
Frank Swygert
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Post Options Post Options   Thanks (0) Thanks(0)   Quote maximus7001 Quote  Post ReplyReply Direct Link To This Post Posted: Mar/11/2012 at 7:19pm
Sounds like maybe the timing advance is sticking sometimes.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 59ramblersuper6 Quote  Post ReplyReply Direct Link To This Post Posted: Mar/12/2012 at 11:42am
I would suspect a clogged fuel filter. I would replace it with a clear one. I have a 59 classic with the original tank. I cleaned it out real well (MEK, Marine Clean) but at this point I think the lead lining is gone and surface rusts is an issue. Right now I'm changing the fuel filter every hour of running or 60 miles. It will clog with rust and block flow to the electric fuel pump. If you get a see-through one (Spectra, Pep Boys, it has a replaceable filter) you can rule out any fuel supply problems.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote farna Quote  Post ReplyReply Direct Link To This Post Posted: Mar/13/2012 at 8:13am
There never was a lead lining. Gas tanks are bare metal inside (well, many are plastic now). There could still be residue from old gas, but the cleaning should have taken care of that. What you need now is a liner to seal the metal and stick the rust down. It should eventually clean out, but doing it like you are could take a while.

Pull the tank and stick a handful of gravel or 3/8" nuts (any odd ones will do, or a short piece of chain) in there. Put in a little water and shake it around as best you can. That loosens all the rust. Wash out real good and let dry. Then get some liner. I use Hirsch Auto tank sealer, but Eastwood sells a sealer that's about the same. DO NOT use the POR-15 liner! It's a polyurethane. If you don't have 100% coverage fuel can get behind the lining and cause it to separate from the metal. The Hirsch/Eastwood stuff is really thin and won't separate. I used a POR-15 kit once, never again! It might work fine with 100% coverage, but that's hard to ensure inside a tank. The 20 gallon kit left a few uncovered spots in my 18 gallon tank. I've used the Hirsch stuff with no such problems, three cars and four motorcycles.
Frank Swygert
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Thikstik Quote  Post ReplyReply Direct Link To This Post Posted: Mar/13/2012 at 6:49pm
have u checked the fuel tank lines?  and hoses?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Pdok Quote  Post ReplyReply Direct Link To This Post Posted: Mar/13/2012 at 9:39pm
Something sticking in the needle/seat?  Had similar issues with a bit of crud in my truck fuel system, but sharp tapping on the Holley cleared the stuff out.

You could also just have a moderately failed fuel pump, putting out low volume, enough to fill the bowl at idle.  Restricted flow or clogs give the same thing, but no way to know unless you go through the whole system and pull lines and check.

Does it happen when the fuel level in the tank is very low, like it could be sucking up some grunge from bad gas?  You said the tank was cleaned, tho.

On the tank thing, I used KBS Coatings tank kit, and I can tell you it absolutely rocks.  It is a very easy process (google their website and watch the videos), and the stuff is awesome.  My radiator shop guy had some bad experience with the POR product, and his eyes lit up when I showed him the test patch I'd put on the back of an old license plate.  You had to use a grinder to get it off...  The kit had about 50% more coating than I actually needed, and I sloshed that stuff at every possible angle for at least 30 minutes, got great coverage inside from a quick visual inspection.

The kit was less than $75, and I did it all in a few days with cure/dry time.


Edited by Pdok - Mar/13/2012 at 9:40pm
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