Distributor Question 2L Aircooled

[veedubtub]

Hi,

I'm wondering if anyone can help. I have a 1981 2L Aircooled with a recon vege engine. Yesterday the van was going along fine when the engine lost power and back fired to a stop and wouldn't start again.
There wasn't a spark from the ignition coil HT lead to the distributor and the plug on the side of the distributor was basically hanging off. The AA guy came out and said that a new distributor was needed. He checked the amplifier and said that was still ok.

My question is, can I replace the broken part of the distributor and not bother getting the timing set instead of replacing the whole distributor and getting the timing set at the garage?

I did notice that you can get a "Distributor repair kit - T3 with vac advance" from Brickwerks.

Thanks,
James.

[Footprint]

Yes, assuming the AA man is correct, the part which is faulty is the Hall sensor, otherwise known as the 'pickup' or 'trigger', and the part in question can be got from Brickwerks, here.
Worth putting some effort into see if it's definitely knackered before you buy a new one though, (search on here and there's plenty to read), as it's quite dear and you can't send it back if you decide you don't need it.

[CovKid]

Worth noting this though:

http://www.thesamba.com/vw/forum/viewtopic.php?t=433661" onclick="window.open(this.href);return false;

[veedubtub]

Hi,

Thanks for the replies. I have taken the distributor out and found one of the wires from the plug to the sender is broken. But I also noticed, looking at the code, that the distributor is the one for a CT engine i.e 070-905-205 Bosch 0-237-023-005‏. The van was going fine. Should I put the correct CU distributor in, what's the advantage or disadvantage?

Thanks,
James.

[Footprint]

Is the dizzy you have double vacuum? Mine had an 009 in it when I got it, soon replaced with the correct one and it gave me an improvement in midrange torque and economy. I don't know how much difference there is between the advance curves of the different distributors, but all aircool VW engines can be fussy about timing, so the right one must be the best option.

[veedubtub]

It's a double one. I've ordered a second hand standard one for the CU so I'm going to try it out! cheers.

[delinkwent]

if it's a double/dual advanced dizzy, then you should need to set it at 5 degrees after top dead centre (atdc)

the timing marks should be visable on the rear of the fan housing (ignore anything on the front if you're not sure they are copies of the marks on the rear)

if you can't find the marks on the fan housing, find the top dead centre (tdc) mark, measure 7.6mm to the left of tdc around the edge of the pulley, make a mark - this will be 5 degrees atdc and the dizzy should be timed

hope this helps

cheers, billy

[veedubtub]

ok, the bus is still playing up. The distributor in it now is for a 1.6 which it was running with fine before. The problem now is that it completely loses power when it goes up a hill. I can make it replicate the problem by driving up a fairly steep hill in 3rd gear for about half a mile under full throttle it then starts to dither and then completely loses power. If I pull over for a few minutes it will then go fine. In fact if it's not under full throttle for a while you wouldn't know it has a problem.

The timing and carbs have been set up by a guy who specialises in vw and 2L Aircooled engines, he has then looked at this issue and can't resolve it!! He thinks it a fuel starvation issue but after tinkering with it for 7 hours and doing test drives he gave up. He has:

Tested it with a gallon can direct as the fuel supply, (skipping the fuel pump and the tank) he also tried this with a 009 dizzy and and it still does it.
He has replaced/checked and set everything in the carbs that it coud be. Jets, filters, float etc. and it still does it.

Since the initial dizzy went I have changed the dizzy for a second hand one, fuel filter and the HT leads (one ht lead did snap on the end, so I put on one of the old ones, but the rest are new).

The vw specialist thinks it might be the carbs but he's not sure.

The problem seems worse when the engine is hot.
Any ideas please?

Thanks,
James.

[Footprint]

Hmmmm... That's a tricky one. If it weren't for the fact that you've run it with an alternative fuel supply I'd be suggesting that as a problem, as it's presenting a classic less than sufficient fuel supply symptom - runs OK but loses power after a short while at higher throttle.

It's not obvious what could be the problem carb wise, as they've been apart and attended to by someone in which you would appear to have confidence, if it were it's difficult to credit that it wouldn't have been discovered after such an extended period of attention. Is it possible that you could borrow a set of known good carbs and try them out? Even if it doesn't solve the problem it would at least rule that out.

[BOXY]

Have you checked the ignition timing is advancing as the engine RPM rises? If the mechanical advance is "sticky" it might be limiting the top end power.