Workhorse 8.1 engine problem/history

[Carvin_Marvin]

Two years ago a friend with an 06 35' Winnebago with approximately 35k miles had two pistons with holes burned through. A short block was installed. Last week, about 8k miles since it was replaced, it started pinging witch quickly developed into a knock. Inspection camera showed #4 with broken upper ring land and pieces of the ring on top of the piston. My 01 8.1 has 101k miles on it. I'm wondering has anyone else had this kind of problem with their 8.1 ?

[ajohnst]

Thanks for all your comments. There are good mechanics and exceptional mechanics. Sometimes it is just a matter of getting lucky at finding one that knows where to look and not just guess. I haven't been lucky enough to find that person. I think the computer may have issues as it didn't throw any codes this last time, but I am not a mechanic and the mechanic I am using now doesn't think it is the computer. Oh well. Thanks again.

[rgatijnet1]

noleakman wrote:
How do you know when you have this problem? Before it blows!

You are talking about a problem that shows up very very seldom considering there are tens of thousands of the 8.1L engines out there. You can add various gauges to your coach to monitor all kinds of things. Some travel with an OBDII gauge hooked up constantly and they may monitor the air/fuel(A/F) ratio and the LF1 & 2 which are the fuel trims. These can tell you if anything is going on outside of the normal parameters that may indicate a problem in the making. To do that, you have to know your engine and know what the "normal" is.
Any engine can have a problem at any time, diesel or gas, Ford or GM. You can go crazy and spend a lot of money to install equipment to monitor everything. Your best course of action is that if something doesn't feel right, get it checked out. If the oil light comes on when trying to exceed 3500 RPM, you have a problem that needs to be corrected. Sensors can and do fail on any engine and anything that is going on that does not seem normal needs to be checked out. The problem is finding a qualified mechanic that knows how to actually troubleshoot a problem instead of just throwing parts at your coach and hoping that one of them corrects the problem.

[hanko]

garyemunson wrote:
Here out west I so often get passed on long uphill grades by those with their foot to the floor, engines screaming, trying to maintain 70MPH. I'm like those above who get many miles of good service out of my rigs because I don't abuse or expect too much from my engine.

me too. guys talk about running their V-10's at 5000 rpm, mines never been over 3500

[noleakman]

How do you know when you have this problem? Before it blows!

[rgatijnet1]

ajohnst wrote:
It was my engine that this happened to. I run premium fuel and never push it. Can't run over 3500 rpm or the oil can light appears on dash. Have had that looked @ several times no resolution. This failure ruled an overheat (blown head gasket & warped head).

Not that it would make much difference but I run regular 87 octane and when in the Western mountains I run 85 octane. I always push the coach when out West because it is fully loaded and always towing another vehicle. I have run close to red line with no problems at all.
Obviously you have some kind of problem that needs a mechanic with the right equipment to find. As I mentioned, I would contact Jon Brazel at (877)786-1576 and see if he can recommend a facility, that they deal with, that is familiar with the GM 8.1L engine. I still lean towards a faulty MAF but it could be an O2 sensor that is sending the wrong info to your engine and making it run too lean, which will produce a lot of heat.

[ajohnst]

It was my engine that this happened to. I run premium fuel and never push it. Can't run over 3500 rpm or the oil can light appears on dash. Have had that looked @ several times no resolution. This failure ruled an overheat (blown head gasket & warped head).

[rgatijnet1]

I have the UltraPower upgrade and am now approaching 90,000 miles with zero problems and most of those miles in the Western mountains with a toad. I have 60,000+ with the UltraPower.
I have heard of some these engines having problems and it is usually traced to a bad MAF. When they replaced the short block for this person I'll bet they used the same MAF.
Have him contact Jon Brazel at Brazels RV Performance and he will explain to the mechanic the problem, and the correct fix.
This is not a problem that creeps up on a regular basis but it is a problem that has been caused before by mechanics that cannot recognize, or know how to diagnose, a bad $80 MAF.

[garyemunson]

Here out west I so often get passed on long uphill grades by those with their foot to the floor, engines screaming, trying to maintain 70MPH. I'm like those above who get many miles of good service out of my rigs because I don't abuse or expect too much from my engine.

[sehunter]

If he bought that used I would make sure that has the original tune in it. Back in the day I heard some horror stories from Workhorse back when they were in that business just as you are describing your friends.

[BigRabbitMan]

MARKW8 wrote:
I does sound like a timing or a lean fuel problem.

Mark

Concur.

[Williebago]

We have 97,000 miles on our 2002 chassis and have had the check engine light come on before and it indicated knock sensor. I usually fill with standard 87 octane, but if I am going to be towing, then I fill with mid-grade 89 Octane fuels. I am trusting their marketing literature that the 8.1 and Allison are a 200,000 mile power train.

[MARKW8]

I does sound like a timing or a lean fuel problem.

Mark

[wa8yxm]

I recall a few years back a post by the rep from Redlands RV.. Redlands is one of the Ultra Power upgrade dealers.

They had, as I recall, half a dozen 8.1's come in with the kind of damage you cit, all of "Warranty age">> Half of them had the Ultra Power Upgrade, half were "STOCK" Workhorse warranted the half that were Stock. but blamed UP for the other half.. (Redlands took care of 'em)

I had a different issue with my 8.1.. Due to an external issue (not an engine fault) IT went BOOM, turned into a "V-6" and sized (Mechanic said there was no evidence of the last two pistons.. I thought there was but he says there was not. Oh well, don't matter) The new engine ..... Purrs like kitten. (And roars like lion going up hills... Just like the old one before the disaster).

[K_Charles]

Whatever the problem was it didn't get fixed when they replaced the short block. It is still the same problem so it didn't happen twice only once. They should find out the cause be for replacing parts again.