Other than to start a p***ing match what is your concern ? are you wondering about a new MH and what engine to pursue. I think that any gas motor out there will due better today than in the past. With that said you are still running a gas motor under severe duty conditions in a MH. I have heard many say that the GM 8.1 litre motor is a very good motor. It can be paired with the Allison transmission.
93 Airstream 35' Dp
5.9 230 uprated to 300 HP
Allison MD 3060
Dutchess and Shadow (fur Bearing Children)
My concern is that I recently purchased a non-runner Class A with 47,000 miles on the odometer and find out today that it probably has 147,000 miles as DMV reported an 'Exceeded Mechanical Limits' - I'd like to get a feel for the sorts of mileages that people get with their gas engined Class As to see whether 147,000 miles on a 454 chevy is something that I should be overly concerned about.
My Jeep has 179,000 miles on it and runs just fine - but it doesn't weigh 17,500 lbs
If I have to budget an extra $2k for a rebuilt engine then I'd better start saving.
Just like your Jeep "it depends", I am sure you know people that have no hope of reaching 100k in their Jeep let alone 179k! If it was well taken care of and not abused should run for a while longer. However if climbing hills like our Grapevine here in So. Cal at 55 and above was a prime concern it could be on borrowed time. Do you have the maintenance records for it? someone that changes oil at 3-5k probably overall takes good care of the drivetrain. Random changes from 5-7k less so, especially if towing to the max of the hitch.
Ray, Cheryl, Cory & of course Miss Molly the four-legged child
What year 454? That makes a difference. When the 454 went to the gen VI there were several improvements made to the lubrication. This dramatically increased the longevity of the engine. The old 454 typical life expectancy was 100K miles, but the later ones could go twice that. Then again, depending on how it was cared for I can give an example of a 455 in a motorhome that lasted 275,000 miles and that was an engine designed in the 60s. There are so many things to factor in. But as a general rule, if it doesn't die soon, I'd be surprised. Especially if it is currently not running, how long has it sat? Did the cylinder walls rust while it sat?
ON Edit: Oops missed it the first time around, I see it is an '84. Start saving your pennies. Crate engine depot has good prices on 502s, that is where I got mine. You need a 502 to move that big of a coach down the road.
Dave
FMCA F298817
'83 Revcon Prince 31' FWD
502 w/Howell/Edelbrock MPFI, Thorley's & Magnaflows,
Koni FSD, Class A built for gear heads ?????? Revconeers Forum
There is nothing compassionate about taking someone elses money and giving to the poor.
I had a friend with a used class C motorhome. It had one cracked exhaust manifold and we broke a couple of exhaust bolts getting the old manifolds off, we had intended to just replace the stock exhaust with new headers. But a friend said you can remove the engine in a few minutes, or struggle with getting the heads off, to rebuild them and extract the old bolts. So out came the engine.
We found out that one of the heads was cracked too. The pistons looked fine, and there was no ring ridge, but the owner was convinced that he could get more horsepower out of the engine, so out came the stock pistons, in went 0.030 over aluminum ones, with balanced rods, flywheel, ect. I guess he spend about $4,000 on that engine.
It would climb with the cruise control on at 65 up 6% grades. The new distributor sure helped out too.
I could see the honing marks in the old 460" engine block, so the short block really did not need rebuilding, but the owner had the cash, so he wanted to spend it, and is impressed with the results. Have you ever heard of a engine that tore the center of the flywheel out of the flywheel? The 6 bolts and pins are left in the center, and the outside of the flywheel was ripped apart, like sheet metal being torn. A heavy duty flywheel fixed that problem.
They started putting in better steel in the early 80's because they needed to pass California's 100,000 mile emissions test. A car must go 100,000 miles and still pass a emissions test to be sold in California.
I would say check the compression, and if it is equal on all cylinders, then keep running the engine. If it is low on one cylinder, then add 1 ounce of oil to each cylinder just before testing that cylinder. If the compression increases a lot, then that indicates a leak past the piston rings.
You might just need to adjust the intake and exhaust valves to bring them closer to spec.
Change the automatic transmission fluid, and make sure that you don't have problems with that transmission too.
I have heard of the engines lasting a really long time. But like you said, the engine was pushing around a really heavy motorhome. Perhaps the original owners already rebuilt it once? Who really knows? You could find out by removing one of the cylinder heads and measuring for oversized pistons, but that cost would be a fraction of the cost to rebuild the engine, to that is not really practical.
I would say move forward with the project, and if the compression is fine, keep driving!
Remember that you may need to rebuild the distributor, the weights can fall off, or the vacuum advance can leak. And you will probably need to replace the carburator floats, as they tend to leak and flood the engine. If flooded, it might start and run really rich when cold, but not run once it is warmed up, and you will smell a lot of fuel in the exhaust.
You might need a timing chain or water pump. Each of these things are a little cost each. I guess that this motorhome can nickle and dime you to death, but it will probably cost less in one year than the payments on a newer diesel RV.
My old Class A MH ( 1978 with 454) had over 200K miles on the original engine when I sold it... last I know ( about 3 years ago) it was still going strong.
Golden_HVAC hit the nail on the head - I only paid $2200 for the non-running coach and have $1500 into it to get it running and replace 25 year old fluids and hoses - new starter/fuel pump/solenoids etc and unravelling 15 years of amateur wiring mods.
My 2002 beaver was costing me $1250 a month and losing money hand over fist and so even if I do have to replace the motor at some point, I'm still doing OK.
Plus I get to turn up at the campground with a clean looking vintage coach
But it's also nice to hear that people have coaches that have fairly signicant miles. I don't have maintenance records but I do have an experienced RV mechanic buried in the middle of the coach somewhere - at least we think he is still in there - no-one has seen him for 3 days
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