rudkevich
Tucson, AZ
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I have a '89 27 ft. class A motor home with a Chevy 454 engine. GVWR is 12000 lbs. An Edelbock (sp?) 4 bbl. carb was put in 3 years ago. The problem I have is that it is horribly slow going up hills but does ok on flat roads. This summer it was doing 12mph going up Vail Pass in Colorado full throttle in 1st gear. The engine felt like it was not getting enough gas. I know this MH is not supposed to be a speed demon, but other RV's easily pass me up going up hills. I checked fuel flow when cranking the engine on a flat surface. It filled up a 16 oz cup in 5 sec. All the electrical and the alternator have recently been redone. So what can the potential culprits be? Fuel pump, fuel filter, vacuum lines? How do I diagnose? Any suggestions would be helpful.
Thx,
Eugene
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DarylD
Coon Rapids, Minnesota
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My guess would be the forward gears in transmission could be going out. How many miles on the transmission? It may need to be overhauled/replaced.
HAPPY CAMPING!! 
Daryl and Sandy D.
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Center Pin
Fort Langley, BC
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Can you pull the plugs and post pictures of them?
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SCOMP225
Brownsburg,Indiana
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I would think that an 80's 454 would pull better than that on hills.
Does it get hot when your pulling hills.The origional Q-Jet might have been richer that your Edelbrock.
I would check the timing, fuel filter and call Edelbrock on jetting the carb.
I'd also check the fuel pressure not just the flow.
If your really concerned I'd put it on a chassis dyno to confirm what kind of power your making and plan from there.
Chuck
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granite
ohio
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2nd vote for the plugs-we had a chevy that age and had to have plugs and burnt out wires to them replaced in Canada on a trip to Alaska, after a similar scenario of losing power on even short hills. Wasn't long or expensive as I recall. Good luck.
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enblethen
Moses Lake, WA USA
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Check to see if you have two fuel filters. One in carb and one on frame rail curb side in front of rear wheels on frame rail.
When electrical was done, was the plug wires replaced?
'89, does it have HEI with coil on distibutor? Connection between coil pack and distributor cap could be attention.
Does it have mechanical advance in the distributor? They could be rusted to the point they don't move.
Do you have the vacuum operated heat riser on the right bank of engine? Is it operating? When it warms up you should see the arm open the heat riser.
Bud
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Jim83Itasca
La Quinta Calif
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Well, If you want to go back through my many post the answer will be there...
I'm still vacationing here in south east Arizona and the climb from the "Coachella valley" (Palm Springs) is dang near a steady pull up the hills.
Steady climbs and a decent headwind all the way (Third gear) produced 7.71 MPG towing a Saturn also....Hope the prevailing wind will push me back home.
Jim
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marvmarcy
Polson, MT, USA
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Lots of good comments so far! Vail Pass is high country and a normally aspirated engine won't perform well. Eisenhower Tunnel is around 11,000' elevation, so the air is pretty thin. That section of I-70 is tough for any engine, but 12mph is pretty slow.
I would have the transmission looked over. The torque convertor and/or clutches may be slipping or the ATF is low. That would cause excessive heat and rapidly lead to failure, but you didn't indicate there was an overheat problem. Do you have a tranny temp gauge or light?
Marv
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AstroBruce
Bucks County, PA
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It's not a fuel filter or fuel delivery problem if it pumps 16 oz. in 5 sec.
If it's not missing or bucking, it's probably not plugs or wires.
I would check the ignition timing and advance.
Might want to check for blocked catalytic converter.
Regards,
Bruce
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1fastdad
mo.
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AstroBruce wrote:It's not a fuel filter or fuel delivery problem if it pumps 16 oz. in 5 sec.
If it's not missing or bucking, it's probably not plugs or wires.
I would check the ignition timing and advance.
Might want to check for blocked catalytic converter. These are good suggestions. If it had a trans problem you wouldn't have made it to the top.
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