Need replacement for Workhorse 8.1 L engine

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morefun

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I have just had my 2004 8.1 L workhorse engine fail with a hole in #2 piston.  I only have 44,500 miles on it and have to find a replacement.  All I can find are Chevy versions of the engine, and a knowledgeable mechanic told me there are differences between the two.  He mentioned a larger oil pan, a different exhaust manifold, different programming, and some other things.

Does anyone know where I could get the Workhorse version from?  If I knew what all the differences are I could probably take those parts off my dead engine.
 

driftless shifter

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Your knowledgable mechanic is either not so knowledgable or wants to buy your rig cheap and flip it. What you want is a long block, with a long block you reuse everything that you have mentioned from the old engine. I doubt Work horse did much of anything to the long block, except maybe spec a truck engine application from Chevy. When researching long blocks ask about the Workhorse application, If there is anything odd about it the reman people ought to know. The engine in my rig is a Jasper long block got about 6000 miles on it no complaints.

Be careful who you pick to do the swap out. The previous owner sold me his rig for the cost of the new long block he had installed. The installer, I won't call him a mechanic, did a horrible job on odds and ends. The engine was bolted in alright but it wouldn't charge the battery, was melting wires and power steering/brake hoses as well as plug wires due to discarded heat shields. he reused the leaking water pump and exhaust manifolds and then the brakes rotted out because the owner couldn't really use it. And somebody fell down on re-coring the plugged radiator so it ran way to hot. Cost me about $4000 in parts and tires mostly brakes wheel bearings and radiator to square it away. No labor charges for the extra work as I was able to do everything myself. Did send the radiator out for re-coring.

Bill
 

kdbgoat

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If you get a new/rebuilt long block, the things you mentioned will have to be used from your existing engine anyway. Replacements should be ordered by using your vin to ensure it matches. If I'm not mistaken,  International bought out Workhorse. Maybe an International truck dealer can help you out.
 

driftless shifter

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I forgot to mention the PO paid $7500 for the long block and installation, in 2010. I have the receipt.

Bill
 

Gary RV_Wizard

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Yeap, all those things are different, but as driftless says, you don't have to worry if you buy just the block and re-use your own stuff.

If you feel you must have a complete engine, an RV salvage yard would be your best bet for the Workhorse configured 8.1L. Two of the biggest are Colaw and Visione.
http://colawrvsalvage.com/
http://visonerv.com/

Raylar Engineering advertises 3 different perfromance-enhanced 8.1L engines for Workhorse motorhome applications.
http://www.raylarengineering.com/workhorse-chassis-motorhome-rv-performance-parts.html
 

John From Detroit

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If there is any difference it is the exhaust header and control computer.

First: a question: have you done any modifications to that engine.. (I really am not interested in the answer for the purpose of htis post but I'm told some of the "Chips" they sell do tend to blow holes in the cylinders.. Just so you knwo)

You have 3 choices

A brand new Chevy 8.1L Vortec (or a Re-man) which you can still buy.. while they last

A used one (I have a lead on one or two)

OR... Power Solultions International 8.8: V-8  Seems this is the same block (one assumes stroked and bored) so it should bolt right in. The exhaust manifold is different. (Center dump instead of rear dump) so some modification of the exhaust pipe is needed (Any decent muffler man can do it) and you may need to move some hoses and/or wires, USE Hight temp spark pulg wires and such depending on the RV.

Or so they tell me.. I would look into that however.

Workhorse is back in business now using the 8.8.. Do not knwo if they are shipping or have contact info.  But likely can get it.

I see Gary give you a link to USED.. Same one I had.

Oh by the way.. Mine through rod #1
 

WILDEBILL308

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Welcome to the forum.
Hear is another option.
http://www.summitracing.com/parts/mll-bp4960/overview/make/chevrolet
Look up one level for list of long blocks.
One outer option is to replace the bad piston if it didn't damage the cylinder walls and save some money.
I think the best is to change the short block.
Bill
 

Charlie 5320

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Seems Visonerv has a pretty good price on a complete take out. If you're not stranded and in a hurry to get it going, I'd have the original rebuilt unless the block was broken when it lost the piston. If it broke the block then there is a chance that the head on that side may also be damaged, then I'd go with a complete engine, but try to find out why it lost the piston. You don't want that again. A bad injector can cause that if you were running lean on that cylinder.
 

morefun

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Thanks to everyone who replied.

I have priced the Vision RV ($2,800) vs Longblocks from many sources (Remanns $3,155  up to GM $4,800), and the used engines are cheaper than just buying a longblock. In addition, there is more labor involved swapping pieces with a longblock than with a used engine, and some of the "remanufacturers" have poor reviews.

It seems that almost no one offers a warranty of any kind for an RV, although a couple will give a limited 60 day or parts only warranty.  Vision RV not only doesn't have a warranty, they won't accept returns either.

I'm waiting to hear back from Colaw RV.
 

thesameguy

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Man, I am kind of blown away by the fact you can't get your engine rebuilt for five grand. A new set of pistons and maybe bearings plus machine shop time isn't $3k much less $5k, and I wouldn't expect collateral damage from just a holed piston.

Given the difficulty of engine replacement on motorhomes, I would *personally* sleep better knowing my motor was done by a qualified engine builder or was fresh from the factory. A used motor that hasn't been opened up and gone through scares the poop outta me!
 

oldme

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In my younger year, I dropped 3 piston one night in a Firebird on a missed shift and inaccurate tachometer factory tech off by 1,000 RPM at 5500 RPM).

Anyway....

A engine tare down found holes in the tops of 3 pistons.
The cylinder walls were checked as were the valves.
The 3 pistons were replaced and I was off and running again.

No need for a long-block or a short-block replacement.
Pistons can be replaced by a decent shop.


 

driftless shifter

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Easy peasy in a car not so much in a MH. You may not be able to get the oil pan off to get at the con rods.

If it was me I'd find the one guy that all the landscapers and contractors go to and pay the money for a long block install. Jasper engine is a nationally known reman company. The sob stories on line are usually related to shoddy installation or owner refusal to spend more money when a quality mechanic suggests new water pump or sending a 20 year old radiator out for testing or recurring while it's out for the engine swap. Either commit and do what it takes or get rid of it.

JMHO
Bill
 

moisheh

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Neither the new Workhorse or Navistar sell parts for Workhorse engines or chassis.
 

WILDEBILL308

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morefun said:
Thanks to everyone who replied.

I have priced the Vision RV ($2,800) vs Longblocks from many sources (Remanns $3,155  up to GM $4,800), and the used engines are cheaper than just buying a longblock. In addition, there is more labor involved swapping pieces with a longblock than with a used engine, and some of the "remanufacturers" have poor reviews.

It seems that almost no one offers a warranty of any kind for an RV, although a couple will give a limited 60 day or parts only warranty.  Vision RV not only doesn't have a warranty, they won't accept returns either.

I'm waiting to hear back from Colaw RV.
If you don't have the ability I would find some one to pull the head on that side. Better yet I would find some one to bioscope the cylinder to see what the damage is. All you have to do is pull the spark plug. If there isn't any major damage then pull the head and drop the pan and replace the bad piston. You only have 44500 miles. You shouldn't need any thing else.
Yes as some one mentioned you may have to take the motor mounts loose and jack the engine to get clearance for the pan removal. Just lightly hone the cylinder walls to let the new rings to seat easier.
Merry Christmas and a safe and Happy New Year.
Bill
 

WILDEBILL308

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moisheh said:
Neither the new Workhorse or Navistar sell parts for Workhorse engines or chassis.
What's your point? It is a  basic Chevrolet engine I can get every part needed to repair it.
Merry Christmas and a safe and Happy New Year
Bill
 

Charlie 5320

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moisheh said:
Neither the new Workhorse or Navistar sell parts for Workhorse engines or chassis.
The Navistar dealer in my city sells chassis parts, don't know about engine parts though.
 

sides

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If your mechanic says the chev and workhorse  motor are different get a new mechanic!! The 8.1 motor is a GM motor period. Workhorse was a GM line of chassis for motorhomes. It was sold off to another entity, and resold, and resold. The 8.1 is different motor entirely  then the 7.4, it looks similar, but the parts are different. 8.1 engine parts and rebuilds can be had it is not hard.  Another thought for the cost buy another Motorhome and forego the problem of engine swap.
 

John From Detroit

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Vision RV is a used parts dealer (Though they can get new and reman as well)

Also the new 8.8L is supposed to be the same block,, From what I am told (Yet to be positon to test) it shoudl bolt in, You may have to move a few things to preotect them from heat and you WILL have to re-due the exhaust pipe since the headers are different but that is supposed to be the ONLY difference worthy of note.  Or so I am told.. When I'm in position to do so Ill do heavier research into this engine.. I suspect you'll also need to re-flash the computers (Both of 'em) but that.. Is to be expectd.
 

morefun

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When I called ColawRV they only had one 8.1L Workhorse engine (65,000 miles).  I guess they don't update their web site very often as it showed several, and didn't show the one he was talking about.

I'm a bit nervous about having the local RV shop try to "fix" my engine.  There are so many stories about poor longblock remanufacturers that I don't know who to trust to rebuild it.  In addition, when the engine started acting up I was on I-81 in New York State on my way to Florida.  I was in the middle of nowhere and since the engine ran fine once I got the RV moving, I continued on to Florida - more than 1,200 miles.  As a result I am concerned about where all the bits and pieces might have gone - places that aren't so obvious like the bearings, so I am hesitant about the idea of "fixing it".  How far do I go - one new piston would not be enough, but how many other things would I have to replace?. 

However you make a good point that I should get an estimate on the cost to repair it, which will of course be higher in labor and lower in parts.

So it seems there are 4 possible solutions:
1) Repair my engine
2) Buy a used workhorse engine of approximately the same year.
3) Buy a used GM 8.1 L engine
4) Buy a longblock

I have time before I need the repair, but I am also living in the RV, which makes getting it fixed problematic. 
 

driftless shifter

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In my mind, the thing about long blocks is more about the installer getting it right than it is about the long block builder. There are many places the installer can make a mistake that can ruin a perfectly good long block. The first thing that comes to my mind is re using the intake manifold with out checking for warping, if it is used warped you will have a vacuum leak that can melt another piston. Oil pump pickup tube not installed properly can give a low oil pressure issue. A used oil pan can have dimpled bolt holes, easily remedied before installation but an expensive repair later to fix an oil leak.  The installers job is more than just installation. The installer has to take a long block, and using various components of the old engine make a turnkey engine out of it. If these components aren't checked for wear or trueness they can fail and take a perfectly good long block along with them. The key is to find a skilled, with an attention to detail, mechanic for the installation, not the lowest price. And you as the owner shouldn't quibble over the price of a part to be sent out for machining or being replaced.

Bill
 
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