hoping the hive mind can help here. Got a customer’s van in. Just put a brand new heritage 1641 in. Stock carb and dizzy. I cannot get it to run properly and it’s driving me mad. When it first started up, it would barely run, with the carb set to the ‘starting point’. I can get it to tick over by winding the mixture and air screws way out, miles past the usual half turn in or out max you normally need. If you’re thinking ‘ airleak’, so was I, so I removed the manifolds, replaced the metal gaskets with fibre ones, no change. Engine out, manifolds off again, fibre gaskets with gasket sealer for extra measure, engine back in, still no change. I can get it to tick over at 850 ish rpm, and when you squirt loads of brake cleaner at the manifolds, the revs drop right down. Got to be an air leak right? But it’s a brand new engine, brand new heads. Manifolds came off a working engine. Manifold boots fine. Could it be new, cracked heads or maybe badly machined faces that the gasket sits against? Any ideas folks?
Pinched tinware under the manifolds. I had to get out the tinsnips because the new aluminium Autolinea cases have rounded fillets in the casting where VW AS41 cases were squarer and thicker.. Also I bet that in your hurry to get your shineeeey wonderful new engine running you pinched the manifold boots underneath.. I did. I could hear it hissing. I Did Not Believe It! So it took a while to find. Its going to be something stupid. I prefer poking around with a hose held to one ear listneing for the harsh hiss of a vacuum leak. Its more accurate than spraying solvents around. That or your petrol pump is knackered and fuel isnt getting to the carb. Ot its knackered and plumbed backwards or using a dynamo 108mm rod on an alternator pump pedestal.
It’s got me baffled. Took the new empi one off to eliminate that, put a solex on that was running perfectly.
Took the Marmitee new cylinder tins off and put some genuine ones on. No difference Likewise, checked the boots, they’re fine. You can spray brake cleaner on them and no change, just if you spray lots on the manifolds the revs drop, presumably where the fluid is temporarily blocking an airleak. Only thing I can think is badly machined surfaces
I should point out, that this the abridged version of events. I’ve already spent ages checking dizzys, carbs manifold boots etc
So you took the Empi carbs off and replaced with a solex one and it ran perfectly, then it's the jets on the carb
No, sorry should have been clearer. I took the brand new empi carb off to eliminate a problem with that and put a perfectly working one on from another van. But it wouldn’t bolt straight on the new engine and work, it would barely tick over, so had to wind the screws out to get the revs up.
I mean it wouldn’t work. It worked on one van perfectly, took it off put it on the new engine and it wouldn’t run. Just did it to eliminate a dodgy new carb(of which i’ve had several)
I thought by screwing the mixture screw out you let more air in ?? If there was an air leak wouldn"t you need to screw it in .?
Could spraying loads of brake cleaner on slow it down by cooling the head rapidly? I’m clutching at straws here
Don't rule anything out. Last year, late at night travelling south on the M25 to get a ferry from Newhaven, we got the full red light and buzzer of doom from our 2.1 wbx. Long, long story short we decided initially to purchase a Heritage remanufactured MV long block for £3200. @davidoft and I fitted it on his drive, Heritage insisted on 500 miles running in before we took the bus through France, Spain and onto Morocco. I videoed ever mile but there was something not quite right, to the point we initially thought the gearbox was rattling. Back up to Aiden Talbots on 3 low loaders to spend the month of March living on an mot ramp whilst we took everything apart trying to find the rattle. We even had the mainshaft in a lathe measuring run out! Nothing, until I was finally checking the valve timing for something to do one evening and we noticed the rear pulley deflecting a bit more than it should have. I got special permission from Heritage to remove the flywheel (it's part of the warranty conditions not to touch it)!, to discover the flywheel had been skimmed on the crank side and to try and compensate the engine remanufacturer had thrown shims at it. Despite the extra, non standard, shims, end float was 3 times maximum wear spec. The crank was floating about, transferring vibration through drive train... To their credit, VWH took the long block back (I obviously had to strip it again...) and we received an immediate refund. There was no place for them to go. I had heaps of video and was in daily contact with them. Eventually we got a gesture of compensation that just about covered gaskets, fluids and seals but despite the qualified engineers recorded measurements of the poor tolerance on the machining and build, the report from the remanufacturer still stated the engine was found to be within spec. God only knows what spec, but it wasn't Volkswagens! Mick at Elite in Basildon stepped up. They have a shocking reputation but he nailed together a long block in 4days for us that did nearly 16k overland last year, 8k of which was mainly off road in Morocco. Won't hear a bad word said against... The lesson I learned was just coz it's new don't mean it's right... Good luck!
Nope. It was a long block, so bolted it in, set the timing, used a pre-set up carb and did the cam break in. I noticed it was ticking over slowly, but thought nothing of it.
Get it out again & on the engine stand, you will have a better chance finding the problem if you are not crouched arse end out of the engine compartment! Also it may have nothing to do with it but we've had long blocks with the dizzy grub screw having been inserted 180• out of sync thus affecting the timing but you said you have set that so .....?
Set the valves. Will it run past 1000rpm then settle down? Or conk out. New dissy fitted I assume. So it ran to 3k for the cam run in ok?
