Hymer 946

[Billstolten]

Hi everyone, I'm new to this site and was hoping someone could help me with a problem. I have the J5 2.5 turbo 1991 Hymer 946 tag axle. It's blowing grey smoke so won't get through an MOT, it's done about 146000 miles, starts and runs fine though struggling up hils, does 65 + on the flat no worries but only has to look at an incline!! ( normal I think? ) is there a replacement engine for this year? Maybe a 2.8 or 3 litre I can put in ? Would an intercooler ( if possible to fit ) make a difference? On a personal note, why would anyone design a 3.5 ton vehicle with such a small engine?

 

[Clivefog]

Dirty air filter , timing out or turbo worn.
My money would be on the turbo.
Do you get black smoke under acceleration?
Do you get blue smoke on start up.

 

[bobandjanie]

I think Malcolm Bolt had one of those, the trouble is it could be a number of things, hopefully something simple like contaminated fuel or blocked air filter but it really needs a proper old school mechanic to look at it, not a mechanic with a laptop. good luck. Bob.

 

[Billstolten]

Hey guys, thanks for getting back. The smoke is always grey, and I noticed that when doing about 60 it disappeared, I couldn't see any smoke at all. It doesn't want to start if you pull out the cold start and it had a service a couple of days before I bought it so the air cleaner should be fine. He had the injectors checked a couple of times ( so he said ) a deisel mechanic friend of mine ( old school type ) is looking at it, he thinks it could be the timing on the fuel pump but any hints.or suggestions from you guys would be greatly appreciated.

 

[tonyidle]

Check the turbo wastegate isn't stuck open. Does the smoke smell of unburnt Diesel?

^{_{Subscribers  do not see these advertisements}}

 

[Billstolten]

Hi Tony, I hadn't thought of smelling the fumes, I will check that out. I will suggest the wastegate but he also said it may be the turbo "actuator arm " ? They get stuck apparently or is that the same thing but different name?

 

[Clivefog]

Sounds like you have someone who knows what he is looking at. Don't assume that a service fitted a new air filter.
Look forward to the diagnosis.

 

[Billstolten]

Your right, never presume anything. Thanks for the input everyone. Will share this wonderful experience when sorted.

 

[Malcolm Bolt]

I think Malcolm Bolt had one of those, the trouble is it could be a number of things, hopefully something simple like contaminated fuel or blocked air filter but it really needs a proper old school mechanic to look at it, not a mechanic with a laptop. good luck. Bob.

I think ours was a B694. It was 1994 and the engine was a 2.5 turbo. Not the best they ever produced. The 5 speed gearbox was in fact a 4 speed with an extra 'bolt on' job. That 5th gear had no direct oil feed, just spray lubrication.

Fiat do not provide any support service for old vehicles such as spare parts and there are so few vehicles with this engine that nobody produces moody spares any more. If spares are required best look to the black country to have something remanufactured.

 

[Speve]

I don’t know if it’s any help to you but there is a very good FB group called Classic Hymers and they seem to have a lot of very knowledgeable folk.

^{_{Subscribers  do not see these advertisements}}

 

[Billstolten]

Hi again everyone, I'm looking for a reputable and fair priced fitter to install an alarm in my Hymer. Or possibly DIY wireless. Can anyone recommend somewhere please? Thanks.

 

[martin2603]

Is the engine using any Oil ? If it is it is likely to be piston rings or wear in the bores.

 

[Portland]

Check the turbo wastegate isn't stuck open. Does the smoke smell of unburnt Diesel?

I back this the older 2.5 was prone to this

 

[Billstolten]

Hi Martin, I've only driven it for about 3 hours so I don't really know, I would have thought that it would be black smoke if the rings were shot, grey smoke is normally fuel? If the compression rings were shot, I would have thought it would run really bad but it does 65 plus no problem.

 

[Figaro]

Have a check on the fiat forum as well as Facebook Hymer classic sites. There are some knowledgeable folk on there

^{_{Subscribers  do not see these advertisements}}