Maybe my engine is different but I just tickle the throttle, ease out the clutch and off we jolly well go ... It honestly seems to have good torque compared to other 1600 vans , pulling away from lights I'm slipping into 3rd as they're still flooring it in 2nd and it'll quite happily trundle along in 4th down to 20 mph AND pick up when i floor it - just an observation . Sent from my SM-G960F using Tapatalk U
Arguably the previous engine with the oil leak ran a bit more smoothly and felt slightly more powerful even. This engine seemed to run rough from the first start. It is better and tolerable but I can’t help but think it should be much better, especially compared to the last Bay I ran. I didn’t clean out the pre heat pipes on the manifold and the previous owner fitted something like a single quiet pack type system that does have pre heat feeds. Perhaps the pre heat pipes are blocked or not lining up with the 4 into 1 manifold. I need to do the cold start and see how quickly they warm up test. The annoying thing is in some ways the engine runs fine but at low revs without WOT the engine hesitates and kangaroos. It seems to struggle up hills more than I’ve previously experienced. I need to check the timing again also. The engine is usable as it is but it isn’t right.
Are you running a standard single carb? That sounds like incredible pick-up compared to my current engine. It struggles in 4th gear even when maxing out 3rd.
Totally stock , svda and single carb - nothing fancy. Not casting aspersions but if it struggles changing up to 4th there's a problem somewhere . Most 1600s have been rebuilt several times over the decades and some will undoubtedly have silly cams better suited to lighter revvier beetles , jetting messed around with etc etc ....Its been said many times , the stock cam setup is good as it gets for a 1600 van and is a pleasure to drive ... (Most of the time ... !!) Sent from my SM-G960F using Tapatalk
Can anyone tell me or give a link to the pre heat pipes check procedure. I read somewhere a couple of days ago that you start the engine and run it for about X minutes and then the pre-heat pipes on the manifold should be too hot to touch. Can’t remember how long the engine needs to run before the pipes should be too hot to touch and also how long it should take for the manifold to be warm?
Just run the engine a bit and see if they heat up. There is no "spec". Having the hot air feed to the airbox is probably more important.
Five minutes should be plenty If the gasses are flowing properly one side should be hotter than the other.
Possibly, but likely the pipes are well bunged up. If they're bolted up, do get quite a lot of heat from conduction.
I somehow don’t think the preheat pipes being bunged up are going to be the cause of a gutless engine. Seems you have spent a lot of time & money on replacing parts when the issue actually lies with the second hand long block. Have you found out what the CC of the engine actually is? Also has it been assembled correctly deck height, compression ratio etc? If you’re not using it much during winter might be worth pulling it out and at least strip the top end for a check.
I don’t think the pre-heat pipes are working. They don’t seem to get hot towards the centre of the manifold and the engine runs better after stopping when warm and then starting again. The 4 into 1 header was very tight to line up with the pre-heat pipes so I’m also not 100% sure how well the manifold is lining up with the pre-heat pipes. The timing I checked today is 8.5-9 degrees BTDC when at idle. Without the vac hose it is 32 degrees at 3500 rpm. With the vac hose connected it goes to 41 at 3800. I haven’t changed the coil or HT leads. I think the carb is icing but still the lack of power does confuse me. If there is a slight incline on the motorway after have to slow down to 20-30mph. It struggles to get beyond 35-40mph with WOT and won’t improve till the road flattens out.
You are describing an engine running on about two to three cylinders, corresponding to low compression. With three cylinders working properly my bus can do about 50mph on the flat, and over 30mph uphill. As tested when I melted a piston . I think your heat risers are blocked or the exhaust was not drilled out for heat risers ( they are delivered as blocked off with an annoying job of making holes into the heat riser connections on the exhaust pipes) But I think you have a vacuum hose swap maybe on the carb.. by the time the throttle is opened up at 3800 rpm under load / wide open throttle the vacuum advance feed to the carburettor should have collapsed, So the advance would be the same at 28-30 degrees with or without the advance hose attached.. the mid revs as you accelerate is where the vacuum advance should be working.. If its 41 degrees at 3800 thats over doing it.. There can be a takeoff for the vacuum feed to the hot air flap that comes off the carburettor. Have a look, you may have that one connected to the distributor, so that as soon as its connected the timing will jump about 10 degrees at idle. The correct timing advance vacuum takeoff should be not sucking (or only slightly) at idle if the throttle plate is totally shut with the idle correctly set by the air and mixture screws.
I think he is measuring total advance centrifugal + vac with no load on the engine so I recon 40 btdc to be about right. 30 degrees centrifugal plus 10 degrees maximum vaccum advance.
Nonsense, the vac advance is unconnected to revs, it's set by throttle position and very low throttle position too. If you are accelerating there will be zero vacuum advance in a bus. It's a very light cruising fuel saving feature that allows a weak (small idle jet) mixture to detonate. You only see it on your timing gun because with no load, the throttle needs to be barely open to rev off the red line.
