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wb13798 · 02-02-2004, 09:23 AM

could some one who has r&r and classic motor home motor describe how to accomplish same and some of the problems to look out for. i am about to do just that and would appreciate any advice i can get.
i have had the front removed to the point i had exposed the front of the motor. replaced water pump and radiator also removed the transmission For repairs.

thenewkid64 · 02-02-2004, 09:42 AM

Al,

I did not do it myself, but the shop that did said once they got to the front of the motor, grill, radiator,coolers, etc out the toughest part was getting a lift to pull the motor. I remember them saying they used a fork lift since the motor could not be lifted too much or it would not clear.

59toaster · 02-02-2004, 11:10 AM

There are a few posts. Most the engine comes out the front using a fork lift or a van hight engine hoist. There has also been some comments that the engine has to come out the bottom on some.
Search for Brett and Edie great adventure. They blew an enigine headed home with a new to them coach and some information is in there.

74Argosy24MH · 02-02-2004, 11:18 AM

Strip the engine to as close to a long block as you can, carb, fuel pump, everything you can take off. Same around the front opening.

A fork lift would be easier than an engine hoist. The upright on the hoist is probably going to be taller than the opening is high so the arm on the hoist will be at a downward angle which hurts clearance. Hook it up as tight as possible, no room for a leveler. It will come out, you will probably have to block it and rehook a time or two. It will help to pull the oil pan and pump if you get really jammed up. Don't try to pull from the manifold, use the accessory mount holes on the front and back of the heads, it will get you tighter down on the block.

Did you give up on the lifters?

John

thenewkid64 · 02-02-2004, 11:31 AM

John just jogged my memory some more.............

The pan HAS to come off to slip the motor out the front. If not you will have to drop the front frame member to get it out

wb13798 · 02-02-2004, 12:28 PM

"no" just looking at the worst case scenario. that seems to be the norm. was going to do a compression test to see if my motor might be worth the effort. if compression is up and good on all 8. i will do the lifter swap. i think 125 on all 8 would be great haven't looked to see what is the norm. if not out comes the motor and down to the rebuild shop. i do know, not much room to do the pull. I'm told the front end has to be jacked up to pull with the shade tree puller. don't have access to a fork lift.

59toaster · 02-02-2004, 01:15 PM

The 454 built up through late 80's had some oiling issues on the cam. This lead to a LOT of flat cams.
If you got the motor apart you might wat to look up the cam oiling mod. Basicly you tap into a oil galley and run a a line of copper or brass over the length of the cam with tiny holes drill in it to spray oil on the cam lops to aid lubrication. Jegs and Summit both sell a kit for this.

wb13798 · 02-02-2004, 04:15 PM

stopped at the parts house to discuss rv heads. final answer was casting no"s are the same as the truck motor. told the manufacture he was a pile of crap would not buy his motor. never had some one play games with motor specs . only difference in the truck engine turns out to be the truck is a two bolt main and the rv is a four bolt main. i guess if it is rv it gets a double the price.
if i do r&r the motor it will be my block that gets rebuilt. that way i know what i have. and that is half the money. and a lot of work.

wb13798 · 02-02-2004, 05:58 PM

forgot to mention compression should be 130 to 150 psi. if not too cold or raining will do a compression test.
the more i dig into this problem i get the feeling it might be a cam lifter problem.
that makes it a $200 for parts job.

74Argosy24MH · 02-02-2004, 06:12 PM

High to low should be within 10% too. How many miles and how much oil does it use?

John

wb13798 · 02-02-2004, 08:35 PM

if i stay under 65 it use very little if any oil. get up at 70 it will use a quart every 500 miles. some of it is coming out the rear of the valve covers. it has always leaked for some unknown reason . i replaced the valve cover gaskets, still leaks some .
i looked up the r&r in the service manual the directions seem straight forward. not much room to accomplish. says remove all accessories and make a pulling plate for the intake manifold. and mount with the carb bolts. don't think i like that .
the procedure for the Isuzu diesel says cut cross member, remove bumper and them you have to take it easy, not much space.
weather permitting will do compression test tomorrow. if compression is ok i will check lift on lifters at the heads, with the valve covers off. should tell me something.

wb13798 · 02-03-2004, 11:48 AM

finished the compression test all have 130 to 135psi except no3 and no 3 and they were 125/127psi. i don't think i want pull this one yet. found a bad plug wire and broke a plug.
what do i do now ???

74Argosy24MH · 02-03-2004, 01:58 PM

Change the wire and plug first, see if it helps. To find out what lifter it is you have to pull the valve cover and start the engine and it is going to be an oily, nasty, smokey mess.

John

dinoburb · 02-03-2004, 01:58 PM

WB13798,

I have read your saga with interest. Pulling the engine with a plate bolted to the intake manifold (if the manifold is cast iron) is the common and preferred way. That is the central balance point.

Replace your cam and lifters. Crane cams has an appropriate dual pattern cam shaft that will measurably improve the torque and HP of the 454. These cams are designed for pulling NOT high end HP.

A truck engine by GM's definition is one used in a 40/4500 series truck or heavier. It typically has a taller deck height requiring truck specific manifolds and other items. GM has never made an 'RV' engine. Your engine is classified as a passenger engine and may or may not have 4 bolt mains. Not to worry. Rebuilding your engine is probably the best way to go especially if a warm engine compression test showed 125-135 across all cylinders. Rebore using a shop that uses a Sunnen honing machine and install hypereutectic (sic?) not forged pistons. Stock compression would be best.

Rebuild the carb or replace with a new Quadrajet, install an aftermarket aluminum intake manifold for the oval port heads (which are the type you have) and a set of Doug Thorley Tri-Y headers and appropriate exaust system. Remember gasses in = gasses out so don't choke the system at any point.

An MSD or Jacobs ignition system would be the icing on the cake as they both make systems designed for the low rpm RV type of engine. Distributor, wires, plugs, & specialized ignition module. MSD makes a replacement system without the multiple spark unit,; that has the increased voltage ignition module which would save $150.00 and still be a major improvement over stock. Old distributors make for poor timing and performance.

The result will be a strong motor that pulls well even in the hills.

Hope this helps some.

txbeaux · 02-03-2004, 02:16 PM

Most auto parts stores have reasonably priced clips for the rocker arms that prevent the oil for getting all over. I built a RV engine using a General Kinectics cam and all new valve train from Jegs. Was priced right and worked good for my application. Still has a little lope to it.

Kinda neat!!! Jim

wb13798 · 02-03-2004, 04:59 PM

the compression test was a cold motor. about 35 degrees. the cylinders that were low might be because it is hard to keep the pressure on the probe that is sticking into the plug hole. was going to take the front tires and fender well s off . to cold and the wind was blowing. did it from the dog house. not much room.
i replaced the bad plug wire and a new set of plugs. it is not bad as it was. motor has quited down some. i still have a knocking noise. but not as loud.
couldn't find the mod kit at jegs or summit . surfed the net and that is a pain to find something specific. if you have a part no pass it on pls.

74Argosy24MH · 02-03-2004, 05:07 PM

Try this. They clip over the end of the rocker and deflect the oil that comes through the pushrod. It is still a messy job, cover everything around or it will be stained. Open the windows or you will get smoked out.

John

wb13798 · 02-03-2004, 07:07 PM

just received a call from a gm heavy truck mechanic who despises the 454. he says gm has made some good motors and the 454 isn't one of them . says a lot were made and they are all junk. and he has seen more than his fair share. discussed my problem and he says i have a cracked piston. cant figure that one out. is that believable???

thenewkid64 · 02-03-2004, 08:16 PM

Sounds to me like a GM hater that wants to make a buck. Or a guy with a 503 sitting in his inventory he wants to sell. Most Mechanics say the 454 is a bullletproof engine to a point. Have you abused it?