Backfire issue sorted (hopefully)!

[300CE]

Thought I'd post this up just in case anyone is experiencing the same issues. I took the van for a run last weekend and had a backfire, then a larger backfire which caused the van to stop. I'd be having hassle with the van ticking over properly from start up and when it did eventually settle, had a slightly erratic tickover.

My mate brought a timing gun from work, so using the Haynes, checked the timing and a slight adjustment was required (was last done about 2 and a half years ago). I also changed the fuel pump with one from Brickwerks and replaced the return fuel hose (Cohline) from the carb.

She's now running much more smoothly and is holding tickover with hardly any erraticness at all. I took her on the same motorway route today and not any sign of a pop or a bang! Will be checking the mixture with an analyser in the coming weeks just to get it spot on.



Would just like to say a big thank you to Paul (itchyfeet) for his helpfulness and advice.

[CovKid]

Paul is one of the good guys.

[Bigjcc55]

Nice clean and tidy looking engine bay.

[300CE]

Nice clean and tidy looking engine bay.

Cheers Bigjcc - I even hoover the bloody thing (sad I know)

[itchyfeet]

I have read you can get problems with damp in the dizzy cap which causes the spark to arc to the wrong plug and fire at the wrong time causing this.
maybe worth a new cap

[300CE]

Cheers Paul - it has a fairly new cap (about 3 weeks) and new rotor fitted mate, but will try and see how she goes in the morning once she's cold and if it's a struggle will have a look inside. No more drips either Paul, but reckon she's deffo pulling in air from the rusted end of the plastic coolant pipe so deffo new one on the list of bits to get

[itchyfeet]

Never assume a new part is not faulty
Are we talking a quality new dizzy cap?
You have to say if you just changed the cap and you then had a backfire the two could be related.

[300CE]

Cap was one of those with the plastic shroud from BW - backfire was after this was fitted so could possibly be iffy. I always carry a spare so will swap over.

[itchyfeet]

I wonder if an HT lead wasn't connecting properly, backfire is often caused by unburnt fuel, if an HT was intermittant it could now have been moved to a good position by you adjusting timing.
All just things to remember if it comes back.

[New Kentish Campers]

Nice clean and tidy looking engine bay.

Shame about the rest of the van.....


Only joking, Justin

[ghost123uk]

Will be checking the mixture with an analyser in the coming weeks just to get it spot on.

Just popped in to remind you that, other than the tick-over mixture, there are no other mixture adjustments that can be made on the carb.
Tis a nice looking engine and bay

[300CE]

I wonder if an HT lead wasn't connecting properly, backfire is often caused by unburnt fuel, if an HT was intermittant it could now have been moved to a good position by you adjusting timing.
All just things to remember if it comes back.

Nice one, thanks again Paul - HT leads are also new along with the plugs so will keep an eye on em' as well. Fingers crossed it's all sorted for the time-being

Nice clean and tidy looking engine bay.

Shame about the rest of the van.....


Only joking, Justin

Hahaha!! Mate's just bought a welder Doug, so might see if he wants a bit of a project. He's just made a trolley for all his welding bits to go on:

[300CE]

Will be checking the mixture with an analyser in the coming weeks just to get it spot on.

Just popped in to remind you that, other than the tick-over mixture, there are no other mixture adjustments that can be made on the carb.
Tis a nice looking engine and bay

Cheers John - thought it may have been running a bit lean upon start up and then leaning out more once up to temp. Will report back with the findings.

[Bigjcc55]

In you're tidy engine bay pic it looks like the cut off valve on the front of the carb is disconnected? Maybe just the way it looks in the picture.?

[New Kentish Campers]

I wonder if an HT lead wasn't connecting properly, backfire is often caused by unburnt fuel, if an HT was intermittant it could now have been moved to a good position by you adjusting timing.
All just things to remember if it comes back.

Nice one, thanks again Paul - HT leads are also new along with the plugs so will keep an eye on em' as well. Fingers crossed it's all sorted for the time-being

Nice clean and tidy looking engine bay.

Shame about the rest of the van.....


Only joking, Justin

Hahaha!! Mate's just bought a welder Doug, so might see if he wants a bit of a project. He's just made a trolley for all his welding bits to go on:

Is that air or water cooled?