# Hymer s660 mercedes help needed



## Claff1 (Jul 19, 2009)

Hi all

I have hymer S660 1988 on a mercedes 309d chassis and a 3 ltr 5 cyl diesel engine.

At start up the engine is misfiring but when temp gets to 80 degrees it runs smooth.

Wondering if anyone has had similar trouble and can shed some light on it.

I have checked heater plugs and relay and ran injector cleaner through plus full service

Help please!! :?:


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## blackbirdbiker (Mar 12, 2007)

Sounds like your injectors need to be serviced...take them out and let a diesel specialist sort the problem.

Keith


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## Claff1 (Jul 19, 2009)

*air in fuel line*

Hi Keth

Dont think its injectors

Had a leak on return pipe on 2 injectors and could hear air hissing after shutting off

Fixed those -- all running perfect even at very low idle

left overnight and problem back next morning so I think its definitely air getting into fuel line

Still looking -- putting on new inline fuel filter tomorrow and a non return valve

Here's hoping

seamus


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## Claff1 (Jul 19, 2009)

*300d engine*

Hi Keith

Turns out you were on the right track

I left in my old Hymer to my local mechanic who is an ex mercedes trained mechanic and I am glad I did.

It turns out I had sorted all air issues but I had not realised there was another fuel filter in canister at engine.This he said was quite dirty so He started there and on next cold start up still had misfire. He then went on to injectors and found no 5 not firing. He pulled all the injectors an on test found no 5 ok but no 3 not up to scratch. He then came to the conlusion that the tappets were getting tight so adjusted them with no 5 being tightest leading to exhaust valve staying open. i am getting her back today and unless valve seating on 5 is damaged I should have a much smoother and more powerful engine back. Some things are better left to the experts! Dont know what cost is yet but whatever I hope it runs well !! 
Will let you know how shes going. Thanks


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## Claff1 (Jul 19, 2009)

*hymer s660 update*

Happy days!!

Got the van back ---------- more power , quieter and probably more economical!!

France here we come!

At least there wont be a load of smoke when we start up on the ferry!

Hope my saga helps someone


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## Zebedee (Oct 3, 2007)

*Re: hymer s660 update*



Claff1 said:


> Hope my saga helps someone


Not in the Lunar Motorhomes forum it won't! 8O :lol:

I'll move it for you.

Dave


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## Chrisatisis (May 15, 2012)

*Mechanic*

Which neck of the woods are you resident. I'm after a good mechanic for my S660?

Cheers


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