Help with the engine in a 2008 Winnebago Adventurer

[Thechap1]

I am currently looking at a 2008 Class A Winnebago Adventurer WPG38T. This RV has the Vortech V8 engine with around 18,000 miles. The RV sat for several years and is being sold at a Chevrolet dealership. I got a call yesterday from that Dealer who said cylinder #8 had developed a miss and they were trying to figure out what the problem could be. As of today they still haven't figured it out. Any suggestions?

 

[DonTom]

I am currently looking at a 2008 Class A Winnebago Adventurer WPG38T. This RV has the Vortech V8 engine with around 18,000 miles. The RV sat for several years and is being sold at a Chevrolet dealership. I got a call yesterday from that Dealer who said cylinder #8 had developed a miss and they were trying to figure out what the problem could be. As of today they still haven't figured it out. Any suggestions?

If the compression is good on cylinder number 8, the odds are it will be some small thing causing the missing such as bad spark plug or bad wire to it.

If the compression is not good on 8, it means a serious problem.

My guess is it's a minor problem, but some minor problems are tricky to find.

But the compression test will tell you if it is a serious expensive problem. Means they need to get inside the engine to fix it. It's less likely than a minor issue, but still possible.

-Don- Reno, NV

 

[Mark_K5LXP]

My observation is that a chevy dealer that needs repair advice for a chevy engine is probably not a resource I would rely on. At best it's low on the priority list and any work they do on it only takes away from resale profit so the best you could hope for is it's a simple/stupid problem to solve and it's not band-aided just to get it sold.

Mark B.
Albuquerque, NM

 

[Gary RV_Wizard]

I am currently looking at a 2008 Class A Winnebago Adventurer WPG38T. This RV has the Vortech V8 engine with around 18,000 miles. The RV sat for several years and is being sold at a Chevrolet dealership. I got a call yesterday from that Dealer who said cylinder #8 had developed a miss and they were trying to figure out what the problem could be. As of today they still haven't figured it out. Any suggestions?

That's a very, very nice gas coach - literally the top of Winnebago's gas-power coach line. But leaving it just sitting around for some years should give you pause because things go wrong with age & neglect. If you decide to go ahead, pay a professional RV inspector to do a thorough job and also have a 3rd party do a chassis inspection.

My guess would be that they haven't even looked for the #8 miss problem yet. The engine isn't easily accessible on a Class A motorhome and the repair isn't urgent unless you make it so. Tell them you won't even consider buying until the miss is resolved.

One caveat: The Vortec engine in an Adventurer means it has the Workhorse W24 chassis. It's a really excellent gas RV chassis, but Workhorse went out of business in the post-2008 recession. GM also halted production of the 8.1L V8 in 2007. That means that new chassis parts are no longer available and the 8.1L Vortec is also obsolete. If the chassis needs substantial repair for some reason, you may be stymied finding parts. This isn't a show-stopper, but it is a concern to weigh into your decision.

 

[Arch Hoagland]

Have the spark plugs and wires ever been changed?

 

[Gary RV_Wizard]

Have the spark plugs and wires ever been changed?

Probably not. They would normally be good for at least 100k miles and since nobody was using the coach, it's unlikely any deterioration in performance would be noticed.

 

[John From Detroit]

When two cylinders on my Vortec V were misfiring (I could hear it but my wife could not) Turns out a rodent had Lunched on the primary wire. Bit of solder and some electrical tape they replaced the two fouled plugs and No more misfire.

But that is only one cause. As I recall that engine each "Coil" serves two cylinders (I might be wrong So since they fire just prior to TDC one firs on Compression one on exhaust (nothing to burn on that stroke) makes the circuits easier.

I'd say that the prime list is plugs. Plug wires. and since it's just one cylinder... Well as someone said if the compression is good that covers most of the "internal" stuff.

But GM did have a batch of bad pistons... Many moons ago.

 

[garyb1st]

If memory serves, certain Vortec 8.1 engines did have a problem with plug wires burning up due to limited space and excessive heat. My 2005 Pace has after market plug wires that were put in more than 50,000 miles ago. So far with 76,000 miles, the engine has performed very well. Prior to the upgrade, the original owner experienced several episodes of engine misfires. It's a relatively inexpensive upgrade.

 

[DonTom]

But GM did have a batch of bad pistons... Many moons ago.

I recall "many moons ago", in the 1990's, when GM had a bad run of camshaft lobes that were too soft and would wear down in 20,000 miles or so to the point where some of the valves would not move. I know about it only because it happened to my GM van back then.

I do not recall a piston issue.

-Don- Reno, NV

 

[John From Detroit]

I do not recall a piston issue.

That was back in the 200xs Redlands told of having half a dozen come in with pistons that had gotten Religion (Holy holey. holes) 3 Workhorse warranted as they were STOCK 3 they refused because they were modified and Workorese claimed it was the mod's fault (Forget the name of the mod Redlands installed) Identical failures on all six.

And that is just one shop.. I don't knwo how many were fixed at oter shops.

 

[garyb1st]

Gary RV Wizard said "The Vortec engine in an Adventurer means it has the Workhorse W24 chassis. It's a really excellent gas RV chassis"

Looked at a Pace Arrow with the W24 chassis before purchasing ours with the W22. I was impressed by the way it handled. Are the handling characteristics strictly weight or are their other differences?

 

[Gary RV_Wizard]

Looked at a Pace Arrow with the W24 chassis before purchasing ours with the W22. I was impressed by the way it handled. Are the handling characteristics strictly weight or are their other differences?

The W24 has a longer wheel base and larger GVWR than the W22, so more suitable for larger/heavier RVs. It also has the more-capable Allison 2000 transmission vs the 1000 in the W22. For 36+ feet in length or over 22,000 lb in weight, the W24 to the best chassis choice. Other than the increased weight ratings, I don't think the suspension & steering design are materially different than the W22. However the longer wheel base and the greater weight of the coach using it will make it FEEL more stable and the steering more sure.