TheSamba.com :: View topic - Hesitation when I accelerate

Mon Aug 11, 2014 6:27 pm

After having just read this thread, it would make me wonder why there would be a problem with the carbs after only changing the trans? Is there a likelihood that the shop that installed the trans messed with the internals of your carbs? It wouldn't seem like they would.

I'd take it to the recognized expert and let him dial it in. He's already shown (evidently, in a phone call) that he is the expert people say he is.

Chuey

Mon Aug 11, 2014 7:06 pm

Yes - the question does seem to be begged . . . what does this issue have to do with putting in a transmission ! ? I agree . . but . . but and I say this with very little respect for the 4 - 5 shops I have let work on my bus. Often when you leave your car to get one thing fixed at a shop . . they mess 2 other things up.

This has been my experience . . not at one . . not at two . . but every shop I have used. So . . in this case these knuckle head smiths left my ignition in the ON position and burnt out my Ignitor one electronic ignition. Called me to tell me the car does not start (and they don't know why !?) and they had to put a NEW distributor in the car . . I show up and it's running like complete shit (and this is a HIGH END German Motor shop in Washington DC . . the lot is filled with Mercedes - Porsche . . etc.) and everything is F#$k up with my VW.

I loose it . . on the spot tell'm I wish they would have told me they know nothing about vintage German cars, send my girl back to the hotel room (on road trip when it broke down) to get my tools and start working on it . . in their bay on their lift. Cursing and ranting the whole time . . it was a scene . . by the end I got it running and the shop owner wanted to hire me. We parted as friends after I got street cred for digging into it and getting it fired up and out of the bay.

I think they might have pulled the carbs off to get the engine out of the bus. I have the standard Kadron Manifolds and the Carbs sit pretty high up. If you drop the engine it's not necessary to pull them off . . but if you do it lazy style and just pull off the skirt and bumper and try to pull it straight out they don't clear the top of the engine compartment. So I don't know what they did . . I know I got it running now and its back to running SWEET ! Going to pull my reduction gear box bearing out this week and replace with new bearing (old ones are tired) so after that I should be "good to GLIDE" with my freeway Flyer and new bearings.

But you know how it is with these little beasts . . there is always something waiting around the bend to be tweek'd and or replaced.

Thanks !

Mon Aug 11, 2014 7:08 pm

Scooter knows carbs. Try his advice and see.

As for oil, I run Valvoline 5W-20 in my 1835 bug motor. Warmed up it makes 18psi at idle. It has a 26mm pump, full flow filter and stock oil cooler. I believe in running the thinnest oil possible to get the desired oil pressure. Thin oil cools better too.

Mon Aug 11, 2014 7:20 pm

Scooter is a trip . . as are most of the Yoda VW types ! He does know carbs . . and he dialed mine in over the phone and told me what to do and not to do.

So . . I've become a believer in all things "Scooter" !

Humm . . I went to the 10w-40 to protect in a hotter climate (thicker better in
hot climate) now you are telling me thinner is better in hot climate ? ! Wow I have to say the oil conversation is ALL OVER the PLACE when it comes to VW's.

Seems like everyone has an opinion that some how contradicts someone else.
I guess I will see how the engine feels (heat wise) running 10w-40. How bad could it be if I'm changing it every 1.5 K - 2K ?

Thanks !

Tue Aug 12, 2014 7:33 am

Oil viscosity choice depends on several factors. Climate, engine condition, oil pump size, extra things needing oil (turbo, piston squirters, rocker spray bars, Bob Hoover mods, etc). The goal is to get about 10-15psi per 1000RPM. My freshly built 1835 with 5W-20 makes 18psi at idle and 50psi at 3000RPM.

By using the thinnest oil possible (but still maintain pressure) I lube the bearings and rockers as needed. Then the nice thin excess oil runs back to the sump very quickly taking heat with it. Heavier oils return to the sump more slowly.

Also, the stock oil cooler control plunger is controlled by oil pressure (not oil heat). When the oil gets hot and thins out, there's not enough viscosity to keep the plunger open so it's starts to close and force oil through the oil cooler. If you use to heavy of an oil, it'll "trick" this design and not start cooling the oil soon enough, leading to more heat problems. Thinner oil on the other hand will not do so.

I'm now adding a turbo so my viscosity needs will change most likely. The turbo requires oil so that'll draw more from the oil system. On top of that, there'll be more heat in the oil and engine area so I'll adjust accordingly.

Get a good oil pressure gauge, a thermometer (for outside air temps) and and a notebook and do some experimenting. Play with different viscosity oils and you'll find the sweet spot.