Engine won’t fire

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itchyfeet
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Re: Engine won’t fire

Post by itchyfeet »

if its dizzy borrow mine until you find one second hand
cheaper than a hall sender kit
my spare has a leaky vac can but easy to swap yours onto it

Worth trying a 12V feed to the coil
I have seen broken wires and duff ignition switches before they show 12V but don't pass current

the stud in the black box is 12 V connect it to black wire on coil with a temporary bit of wire.
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Snowmark
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Re: Engine won’t fire

Post by Snowmark »

Looks like Sunday is going to be a busy day of trying stuff, swearing, rereading this post then swearing some more.....
1986 1.9DG WBX Autosleeper Hi Top

Sir Brixalot
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Re: Engine won’t fire

Post by Sir Brixalot »

Had a month of those Sundays myself
Honorary "Dave" 

 

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itchyfeet
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Re: Engine won’t fire

Post by itchyfeet »

Snowmark wrote:Looks like Sunday is going to be a busy day of trying stuff, swearing, rereading this post then swearing some more.....

Don't worry it can't be that hard to fix with a bunch of spares.
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diabolov
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Re: Engine won’t fire

Post by diabolov »

Hi snowmark,

just thinking that if the plugs are wet then you know you have fuel getting to the combustion chamber, so must be spark issue. we know the pump works but could be a blocked primary jet or stuck float valve stopping it getting further. How about the small filter in the carb inlet blocked(assuming it's a pierburg?)
We all know you need air, fuel and a spark to make a bang. Air you got, fuel not sure past the pump, and spark you are checking on. I'm no mechanic, and some on here have more of an idea then me but the more you can eliminate the narrower the field of what it could be. So if you eliminate fuel supply then it has to be electrical.

Just my thoughts

Sorry can't be more help.

Regards
Mark
Autohomes Kamper 1986 WBX 1.9 DG

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Snowmark
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Re: Engine won’t fire

Post by Snowmark »

Many thanks for the input, Mark.
Yep, it’s a pierburg. I fitted a brand new cone filter just last month and have the carb rebuild kit in my shed at home waiting until we’d finished camping - looks like that time is now!
Once home I’ll swap the coil and dizzy for what will hopefully be an ‘easy’ solution - if not then it probably is a carb issue.
Thanks again, really appreciate it.
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300CE
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Re: Engine won’t fire

Post by 300CE »

I’d take up Itchy’s offer of borrowing his dizzy and just swapping the vacuum unit over. Easy enough to do and should hopefully help you avoid too much swearing!

Might also be worth investing in some of these for your spares kit:

https://rover.ebay.com/rover/0/0/0?mpre ... 1621717971" onclick="window.open(this.href);return false;

Good luck and keep us updated :ok
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itchyfeet
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Re: Engine won’t fire

Post by itchyfeet »

I can fit a twin vac on the spare DG dizzy it will do the same job ( you just conect only one vac port) that way you just have to swap it to see it if works.
changing a vac can is easy but only if you know how.
don't pull the old one out until you have got the engine to TDC on No 1, i.e. the rotor arm is pointing to No1 plug lead, then it's easy to get the replacement in the same position
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Snowmark
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Re: Engine won’t fire

Post by Snowmark »

Looks like I’m heading over to Paul’s at the earliest convenience with a large van......
Paul - I’ll pm you later as we sit in various Service Stations trying to entertain two children for hours on end!

Looks like all this will have to be done on the road at home as I doubt the RAC will get me back on the drive.....at least the weather hasn’t taken a turn for the worse
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itchyfeet
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Re: Engine won’t fire

Post by itchyfeet »

This is why I keep spares of everything, so much easier fixing a fault by swapping known good bits.
Just fitted the vac can to the dizzy.
did you manage to get a 12V feed on the coil? it could be as simple as an ignition switch faulty?
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Snowmark
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Re: Engine won’t fire

Post by Snowmark »

Not looked at much since the RAC guy left - took the kids out for the day and ate ice cream. We are due to start the first leg of the journey home by 10am to Exeter Services then an undetermined wait for the next truck.
I’ll run through basic checks tomorrow morning- I have a new ignition switch if needed, try the new dizzy cap and leads etc.
1986 1.9DG WBX Autosleeper Hi Top

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itchyfeet
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Re: Engine won’t fire

Post by itchyfeet »

Got this ready for you MArk

a complete ignition system up to dizzy which will prove if yours is faulty, just add 12V from the stud in black box and give it and earth, just tested it works on the tin top

ImageP1100713 by Paul_Barr, on Flickr

failing that change dizzy still no joy try carb.

ImageP1100714 by Paul_Barr, on Flickr
1988 DG WBX LPG Tin Top
1989 DJ digijet WBX Holdsworth Villa 3 Pop Top
itchylinks

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Snowmark
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Re: Engine won’t fire

Post by Snowmark »

Update: Following considerable help from Paul and a very soggy afternoon......nothing has changed!

I bypassed my ignition system initially and used the one that Paul had kindly rigged up - still the same problem, pops from the exhaust but the engine won’t fire.
I then wrestled with my dizzy for a while as the pinch bolt had completely rusted in and was very bent. Ended up having to drill the old one out and straighten the bracket. Replaced my coil but changed the dizzy, manually set the timing by feeling for compression on cylinder one whilst turning the crank by hand and lining up the rotor arm to the position of lead 1.
I was convinced this would solve the problem as when I removed the original dizzy the base plate had significantly more lateral movement than the one Paul had lent me - it just felt worn and loose.
Anyway, turned it over and nothing........
Then the Heavens opened in a Biblical manner and I scooted indoors and had a scone.
I have been given the day off from parenting tomorrow so that I can have all day swearing. Just been back out and checked the voltage to the coil on ignition - only getting max 10v from the double black wire to the coil on turnover.......question is, is this enough?
Thanks for everybody’s help up to now - please keep throwing ideas in as I need excuses to avoid days out during the Summer Holidays
1986 1.9DG WBX Autosleeper Hi Top

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itchyfeet
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Re: Engine won’t fire

Post by itchyfeet »

As said charge the battery over night and look again tomorrow it will probably be low by now.

Try both my dizzy and coil setup powered from the stud, I'm confident they work.
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937carrera
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Re: Engine won’t fire

Post by 937carrera »

Back to basics then, some thoughts for you

You need air, fuel and a spark at the right time.

Air isn't usually a problem

Make sure the engine is at tdc by reference to the notch on the edge of the distributor and by putting a longinsh probe down the spark plughole. I have a favourite screwdriver that I use, some people will frown on this usage, but I have never had a problem testing for tdc this way. So long as ignition timing is TDC + / - 10 degrees she will fire if everything else is OK

Check that each of the plugs is sparking, nice and blue, rather than yellow, regular too.

If you have a spark, then the problem is fuel. Try the petrol down the throat of the carb method, you'll usually get a response and run for a few seconds with no fuel to the carb.

As said earlier, if it still doesn't fire, then see if the plugs are wet, have a sniff. I suggest you clean them first, but not strictly necessary. No fuel then look to blocked jets or more likely anti dieseling valve not working correctly.
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