Constant Backfiring

[Novice in need]

Hi all im back with another request for help please.

My van is constantly backfiring (idle & under load) it started out of the blue yesterday, iv checked the basic's connections to carb and changed HT Leads & under dizzy cap. Wondering if its something to do with the exhaust and if so where do i start to look?.

All help & suggestions are really appreciated, Thank you.

[Ian Hulley]

Air leak into the exhaust would be the first place I'd be looking.

[72BUG]

Check for holes in the exhaust. That caused mine to backfire terribly. Replaced the exhaust. No more problems.

[Novice in need]

I am thinking that that is the case, however how would i start to locate the leak? any tricks or tips? should i go round the joints spraying WD40 or is it a case of going the full hog and replacing the whole exhaust (expense i could do without to be honest).
Thank you for your replies.

[Ian Hulley]

Traditional way is to have someone hold a wet rag over the end of the silencer while you look/listen underneath for escaping exhaust gas. It may just be the cast knuckle that's gone ... a common occurance.

Part #5

If I was replacing an exhaust on a 1990 DG I'd be investing in a Brickwerks stainless sytem and possibly having it fitted professionally by them, DO NOT let the witless chimps down at $h!tfit anywhere near your van !! Although it may be amusing watching them try to find the bonnet catch

Ian

[Novice in need]

Thanks Ian,
il get the wet rag out & have a go. Il contact Brickworks for quote if i have no joy in locating the problem.

[kevtherev]

I would brace yourself for something a little more serious though, constant BF is also caused by poor compression due to stuck or burnt valve and poor timing.

Is the backfire constant?
Does it backfire or pop more as you run it up?
Does it stop if you remove a lead?

I've run my engine with no exhaust and it didn't back fire

[jpee]

Don't know what the JK stainless exhausts are like, but they are doing them on a pay them up deal.

[Ian Hulley]

Don't know what the JK stainless exhausts are like, but they are doing them on a pay them up deal.

From past experience I wouldn't trust the JK catalogue to fit right let alone anything in it

[jedijim]

f I was replacing an exhaust on a 1990 DG I'd be investing in a Brickwerks stainless sytem and possibly having it fitted professionally by them, DO NOT let the witless chimps down at $h!tfit anywhere near your van !! Although it may be amusing watching them try to find the bonnet catch



i like the chimps at "pooh" comment lol

[CovKid]

I never get anyone to fit something for me. Much prefer knowing whats been done and do it myself but I agree on Kwikfit - you opught to see them fit a Beetle exhaust - its a hoot

[Novice in need]

Thanks everyone for the replies,

Kevin it pops when reving it up, however still sounds like a tractor even on tick over. I have not taken a lead off to check if that makes any difference, il do that today or tomorrow. Fingers crossed it isn't anything more sinister, i was just about to buy the exhaust gaskets and new bolts and start taking it apart to inspect each section as i cant find the area it is blowing from.

New shiny exhaust is out of my price range

Regards

Zoltan

[Novice in need]

Pulled the leads off one by one and the tractor sound is still there, so i do believe that it must be the exhaust.
Well another winter day spent under the van is to be had