Apologies, this is a cross post as I've also put the same shriek of help on The Late Bay... comes from having a Crossover... but I'm hoping that more of you wonderful folks will know the Type 4 engine well... so here goes Can I please ask for a little help? My van has a 1700 CB engine, it's not running too well and I think I need a little help from those more experienced than me in the ways for the Type 4... The symptoms: Van was bogging down and not revving cleanly, had to give it a fair old push on the throttle to pull away cleanly and then lately I've had a problem with it idling and then dying away... not stalling but dropping right off and then coming back... like hunting in slow motion. What I've tried: Carb completely stripped and cleaned and set up correctly Points set correctly 0.16" Timing set correctly 0.06" What I haven't done yet: Replaced all of the inlet manifold gaskets and boots - haven't ordered the bits but am going to What is giving me gyp: Timing... WTF???!!!! According to my light (Gunson variable, set to 0 degrees) I'm something like 30 degrees BTDC at 2500 - 3000 rpm, Muir reckons 10 degrees ATDC!!! I am *very*sceptical about my ability to time this right... there is a notch on the pulley highlighted with red paint and that's what I'm measuring against, but am concerned that the pulley could be on incorrectly... I'm frightened of bad timing, Type 1 engines are nice and easy in this respect... the Type 4 is intimidating me. The distributor catches on the breather, which is ringing alarm bells, I can't imagine VW fitting a dizzy that fouls... What gives, gurus? What's non-standard: The van has a 32/36 progressive Weber - I think should be twin Solex originally... but it ain't now. The van has a weird distributor with two vacuum pipes... the rear one is attached via a hose to the Weber... the one on the round thing (diaphragm?) is open to atmosphere Speculation: Carb icing... it's been cold and the problem has been worse since... I might have chance of some Weber ICTs and am toying with this idea as I hear that the single progressive Weber and the Type 4 don't play nicely. Manifold leaks... could be, and makes sense of the "hunting" Carb still dirty... nobody is infallible, right? I might have left some muck in there. Timing wrong... could be, I really feel very uncertain about this. How embarrassing... I am actually kind of on a knife-edge with this van now, as I'm about at the end of the remedial work. The reason I'm so keen to get it sorted is that we're going to EBI and then on to Chamonix for a couple of weeks. There is a bit of me that wants to slam the van, there's a bit of me that wants to put a Type 1 motor, there's a bit of me that just wants to send it off to see Daz at Aircooled Engineering and pay someone else to fix it... there's a bit of me that wants to stick it in the For Sale section and get the T25 diesel that I was *going* to buy after selling my Split... existential crisis, dudes... help me out. I know if I just get it sorted then I'll be back in the groove but I'm really frustrated by my own limitations of not knowing the Type 4 engine the way I know a Type 1. It's like being lost in a familiar place... Help :|
looking on www.type2.com, the twin vac dizzy is indeed correct (our FI westy has one)..here is some text: "Over the years, many a 71-74 Beetle and 71 Bus with Dual Diaphragm Distributors have graced my doors and about half the time the vacuum lines are backwards. So here's the poop: First, take a look at your Vacuum can. On the flat side of the can is a hose fitting - for the larger (4.5mm GREEN) hose. This is the RETARD side. Second, on the cone (or rounded) side of the can is the smaller hose fitting. This uses a 3.5mm hose, usually black. This is the ADVANCE side. Third, look at your 34PICT Carburetor. The fitting on the LEFT side of the carb is for the ADVANCE side of your Vaccum can. Connect appropriately. Fourth, look at your 34PICT Carb again. On the rear (RIR) of the carb should be a fitting up towards, but not on the carburetor top. This push-on fitting is just slightly larger than then one on the side. This is for your RETARD side of your Vacuum can. Connect appropriately with the 4.5mm Green Hose. Fifth, Any other fittings on your 34PICT Carb are for the infamous Throttle Positioner sometimes improperly called a "Decel Valve". The fitting for this jewel is an angled one right at the rear base of the carburetor. Connect the small vacuum hose to it to the Throttle Positioner Diaphragm Fitting. If your Throttle Positioner has two fittings (as original on 71 Buses, 71-74 Beetles), connect another length of 3.5mm vacuum hose from that to the Throttle Positioner Solenoid, usually located in the left side of the engine compartment. If you don't have the Throttle Positioner, cap off all the remaining fittings on your carburetor. If you're running one of those new replacement H30/31PICT carbs, the procedure above is the same as they come with these fittings like their distant 34PICT cousins. Original 30PICT Series did not have the RETARD fitting, except for Beetle Auto-Suck Models - BUT - this fitting was for the Auto-Suck Solenoid, not the distributor because they were still single vacuum models (Actually, the Auto-Suck use a combined vacuum/mechanical distributor similar to the 76-78 Buses). Buses don't have these, right? So use this fitting for your RETARD side of the Dual Diaphragm Can. Timing is usually 5 degrees AFTER Top Dead Center when using a Dual Diaphragm Distributor, give or take a degree or two - no two engine setups or running conditions are the same, so you''' have to fool with with of course. One other thing - Strobe Light at idle speed with the hoses CONNECTED. Sorry, no static timing with these, except to initially set the distributor at 0 TDC, start the engine, then strobiscopically time it after it warms up. For those wanting to put a stock push-pull distributor back on their 71 Dual Port 1600 with a 34PICT (or other Bus with the same arrangement, here's the skinny on interchangeable distributors. All have the same Advance/Retard Curve specifications: Vacuum: 2-5deg Adv @ 6.7 In. Hg, 11-13deg Ret @ 9.1 In. Hg Centrifugal Advance: 6-12deg @ 1500rpm, 22-25deg @3800rpm Distributors: 211-905-205Q * 0231 167 055 (Stock T2 '71) 211-905-205S * 0231 173 001 (Stock T2 '71) Note: Originally equipped w/Speed Limiting Rotor, but can use a regular 04 033 Bosch Rotor) 113-905-205AH * 0231 167 053 (Beetle Auto-Suck 71-73) 043-905-205D * 0231 176 033 (Beetle Auto-Suck Calif. 1974)"
Static time your motor to 7.5 deg before tdc. If your unsure how to do that then ask. If you strobe it with the vac hose off at a high tickover. whack the vac line back on max advance (ie btdc) will be around low 30s hopefully. Forget the ATDC as your retard can isnt connected (mine isnt either) Unsure what your issue is but unlikely to be carb icing. Got same set up and all i have to do in winter is increase the tickover as the idle is too low when it comes off choke as the engine isnt hot enough. Does sound like a fueling issue though. Guessing its not overly terminal and it might be best to get it fettled but have a go first!! I do have some blurb on setting your carb up. Haynes manual gives good enough infor on service items so cant be that difficult.
Get a proper dizzy and time it to 7.5btdc .... You will have probs with the carb also . Check for vac leaks
if you are doing the manifold rubbers then I used the silicon (red) ones. They are the same rubber as on a 1600 twin port motor! Might be used on other motors too but i know not a lot about type 1s. Where in the country are you?
I can highly recommend the accuspark distributor from Ebay, electronic ignition already fitted to it and its pretty cheap too.
