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 10/9/2008 11:06 AM
 
Hello All, I am new to this site, and new to r.v. life, so far, I think I might be better off and money ahead to park it in a field and set it on fire. It's a 1988 Champion LaSalle 32 foot class A. It has an engine that was replaced in 2000 or 2002, not sure which. We have been chasing a problem around in circles and throwing money at it but still not have the real problem fixed. Here's the scenerio: After about 800 miles I simply lost all power while driving down the freeway. So far I have had a new alternator, new starter, new ignition relay module, new engine idle control motor, new starter solenoid, new battery, various vacuum leaks plugged and still have the problem. It also idles super high, about 1,400 rpms and runs hot. In reality, I think there has been a LOT of guess work done at my billfold's expense. There has been general talk of hot start relay issues, possibly needing a heat-shield of some kind for something I don't know what, I am an artist, not a mechanic. So the long and the short of it is now they are thinking that the exhaust manifold gasket needs replacing. This, and $3,500. already put out, will it solve my problem? -Drew[font=Comic Sans MS]Text[/font]
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 10/9/2008 12:36 PM
 
Drew,
As a shade tree mechanic my opinion is the exhaust manifold wouldn't cause the symptoms you describe, although it could be a result of the ongoing problem. I'm guessing here but I think it could be one of two problems. Either a vacuum leak somewhere that hasn't been found yet, making the engine run a lean fuel/air mixture and causing the loss of power and overheating, or (something that happened to me years ago) a distributor advance linkage problem. In my case the mechanical advance linkage came apart, allowing the timing to change significantly, causing the severe loss of power and the engine to overheat.
Hope that helps.
Ron
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 10/9/2008 12:36 PM
 
Drew - That vintage Chevy 454 had a problem with burned sparkplug wires. Have they been changed? - Good luck. - Dave

Webmaster Rvamerica.com Support@rvamerica.com
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 10/9/2008 3:14 PM
 
I can testify from some miserable experience regarding the heat problems for that engine and the need for some shielding, but I don't think that would cause the engine to just lose power while on the road, at least mine never did. Once stopped, my Chev/GMC just would not start, but it never quit while running.
I'd suspect one or more of the issues brought up by others, plug wires, vacuum leak, or timing/distributor. Dutch '07 Allegro Bay 34' '03 Honda CR-V

Dutch '07 Allegro Bay 34' '09 Honda Fit Sport Whatever hits the fan will not be distributed evenly
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 10/9/2008 4:17 PM
 
Wow, I don't know about the spark plug wires. And the linkage idea is a completely new one. Is it more or less expensive than the manifold gasket job? Just wondering? -Drew
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 10/9/2008 5:14 PM
 
Drew,
Either spark plug wires or fixing the distributor will be cheaper than paying someone to replace the exhaust manifold gasket. Many people replace spark plug wires themselves as it is not that difficult. Just do it one wire at a time. In my case, fixing the distributor was easy as well. A retainer clip came off allowing the linkage from the vacuum advance diaphragm to distributor mechanism to come apart. Once I found the problem I simply re-assembled it and put a new retainer clip on it.
Good luck,
Ron
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 10/9/2008 6:38 PM
 
Thanks, Ron. I'check into that. It sure seems a whole lot easier than the gasket for sure! Thanks! Drew p.s. Are R.V.'s always such a big headache? This was supposed to be fun.
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 10/9/2008 7:22 PM
 
As well as replacing the spark plug leads,a good 8 or 10 mm diameter plug wire thats heat resistent will work,btw they aren't cheap. In the early years the 454 had intake manifold vacuum problems in the form of hairline cracks undetectable to the naked eye. Then there's always the timing chain could have skipped a tooth or is simply worn out or stretched enough to cause a skip in timing. Have someone check the enine timing. The easiest way to detect a manifold crack is to allow it to idle then slowly spray carburetor cleaner or WD-40 will work, spray small areas listening for an increase in idle rpm's, if a crack is present the intake manifold will need to be replaced. Stock equipment isn't necessary, most any high quality after market manifold will suffice. Neil

Neil
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 10/9/2008 9:17 PM
 
Hello Again All,
I was just wondering if anyone might be located anywhere near where I am located in Northwest Washington State, out in an area called Seabeck near the Hood Canal?
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 10/9/2008 9:28 PM
 
I had a 1986 Georgie Boy w/454 engine. When the plug wires went bad the engine would act like it was missing while in cruise control and trying to climb a small hill. I use the best plug wires from Auto Zone because they would replace them if they went bad again.I drove the vehicle 95K miles and replaced the plug wires 3 times. Because of the heat I also went thru starters.I also had a clogged radiator which caused over heating problems. Keep having fun, Virg, Fountain, CO

Keep having fun, Virg, Fountain, CO
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