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Sun Jun 22, 2014 3:56 pm

so I've rebuilt the carb. Adjusted ran 500 miles. Stopped. Clogged main jet plus dry bowl. Cleaned again, fresh fuel pump, lines, and filter. I've done the 2.5-3 turns out on the main mix (tiny screw). Any suggestions for finding the sweet spot on the carb. it's a 30/31 009 dizzy. runs strong but kinda hot. Hot as in i can't hold the dip stick without a cloth in my hand. drove it!

old carb

new carb

timing and valve adjustment are set. its the turning of the screws i need help with. I need help screwing around.

Sun Jun 22, 2014 4:18 pm

http://www.vw-resource.com/carb.html#brosol

Here's a good start to help guide you on the carb adjustment. You should post a picture of your engine and give the particulars of it. What size, cam, and you running a thermostat, flaps, etc..

How's that carb jetted? How's the 009 timed? How did you do it? The big rocks for over heating are typically, timing issues, missing tin, running lean, etc..

Sun Jun 22, 2014 7:35 pm

1600sp. Timed with a light. Full advance without any stutter. It's e carb adjustment that is bothering me

Sun Jun 22, 2014 8:07 pm

What's your max advance at high rpm?
Does your timing light have a degree dial?

Sun Jun 22, 2014 9:03 pm

Have you out a CO sniffer on it to see what your AFM is? LM-2 meters come in handy for home diagnostics.

Sun Jun 22, 2014 10:18 pm

When I used to use 009 distributors in my bus engines, sometimes, I set the timing at 31 degrees btdc at full out (3500 rpm?).
I gave the 1600cc singleport engine in my bus a tune up, a while ago, and I read that the 30/31 carburetor only has the big screw in the carburetor adjusted to set the idle; the small screw is set at the factory and should not be adjusted.

Mon Jun 23, 2014 5:49 am

Campy wrote: When I used to use 009 distributors in my bus engines, sometimes, I set the timing at 31 degrees btdc at full out (3500 rpm?).
I gave the 1600cc singleport engine in my bus a tune up, a while ago, and I read that the 30/31 carburetor only has the big screw in the carburetor adjusted to set the idle; the small screw is set at the factory and should not be adjusted.

The 30/31 has both the volume control adjustment and an air bypass screw. Both of which you adjust while setting the carb up. You adjust these two screws just like you would a German 34 PICT-3

Mon Jun 23, 2014 6:32 am

Running and warm- adjust the small screw out till the motor bogs- set big screw to 800 rpm - now move small screw in till engine is racing a little and bring idle back down with big screw--- repeat untill engine is boging due to lean idle- back the idle mixtur out to bring idle back up to 800/900. Repeat till stable.

Rev to 2000 and smack your hand over the carb till it dies- then throttle up and crank to start.. That may clean up any varnish/crud shaken loose when adjusting- If it changes- do it again- usually takes a few times to get it clean and right.

Mon Jun 23, 2014 7:17 am

williamM wrote: Running and warm- adjust the small screw out till the motor bogs- set big screw to 800 rpm - now move small screw in till engine is racing a little and bring idle back down with big screw--- repeat untill engine is boging due to lean idle- back the idle mixtur out to bring idle back up to 800/900. Repeat till stable.

Rev to 2000 and smack your hand over the carb till it dies- then throttle up and crank to start.. That may clean up any varnish/crud shaken loose when adjusting- If it changes- do it again- usually takes a few times to get it clean and right.

This is helpful. Carb is clean inside and out. I've taken it apart 3 times in the past 3 weeks. my timing light does not have a dial John but I have marked the pulley.

Mon Jun 23, 2014 8:19 am

Are you sure it's your carb setting that's making you run hot? - you'd have to be running pretty lean (any vacume leaks?) for the carb to be at fault for overheating the engine.

All the rest of your cooling and exhaust systems are in good shape (cooling flaps, thermostat, hoover bit, oil cooler, all tin in place, no exhaust leaks)?

Your timing can more easily affect operating temps - too much advance will make it run hot. I've seen all sorts of timing numbers with the few 009s I've toyed with. You are better off timing them by hear/feel and use your timing light as a rough guide and recording tool - set the timing where the engine sounds the happiest at low idle and top speed. Drive it and see if it feels right - double check with the timing light and record the number somewhere - live with it for a week and see if the engine is cooler or hotter - toy with it some more - repeat as necessary...

Mon Jun 23, 2014 3:51 pm

marklaken wrote: Are you sure it's your carb setting that's making you run hot? - you'd have to be running pretty lean (any vacume leaks?) for the carb to be at fault for overheating the engine.

All the rest of your cooling and exhaust systems are in good shape (cooling flaps, thermostat, hoover bit, oil cooler, all tin in place, no exhaust leaks)?

Your timing can more easily affect operating temps - too much advance will make it run hot. I've seen all sorts of timing numbers with the few 009s I've toyed with. You are better off timing them by hear/feel and use your timing light as a rough guide and recording tool - set the timing where the engine sounds the happiest at low idle and top speed. Drive it and see if it feels right - double check with the timing light and record the number somewhere - live with it for a week and see if the engine is cooler or hotter - toy with it some more - repeat as necessary...

I turned down the timing and that didn't seem to help. Ran hotter! So I pulled over advanced it slightly and fiddled with the bypass screw a tiny bit and it responded much better at take off. Drove home and its hot but better than yesterday. The temp still worries me. This is a pretty worn-in 1600sp with around 45,000 on it. Just trying to make it last.

Mon Jun 23, 2014 6:46 pm

a broken in engine should run cooler if anything.

what size main jet?

double checked for vacuum leaks?

if you look at the a/f curves there is a sweet spot where leaning it out starts to run cooler again. search for wideband in the performance forum to learn more. Dipstick test is kinda arbitrary, look for trend with an oil temp gauge.

Tue Jun 24, 2014 6:48 am

its a 120 main in there. I will do a carb cleaner vacuum check later to see if its sucking in anything around the carb. I've got a long trip to maine planned with the lady and don't want this thing overheating on me.

Tue Jun 24, 2014 6:50 am

post pics of your motor.

Tue Jun 24, 2014 7:52 am

Holding the oil dipstick is not a good way to tell.

When engine temps are 180-200F (normal) there is no way you can hold onto the dipstick.

If you spit on the engine case (or a little water) and it boils off, your motor is hot.

I run an oil temp gauge and just watch it if I am on the highway going fast.

Tue Jun 24, 2014 12:18 pm

Did I miss it? How are you measuring your current oil temp? As mentioned, feeling the dip stick has no value. Can you go to Wal-Mart and buy a turkey fryer temp gauge that you can slide down your dip-stick hole? You need to know exactly what the temp of the engine is to be sure you really have an issue with it.

A 120 main is a beat small for a 1600 in that Brosal carb. I think a 125 main would be about right for that set up in your bus.

I don't think this is your issue, if it's running too hot. As Clara asked, post a pic of your engine. Does it have the cooling flaps and thermostat? Is ALL the tin in place on it?

Tue Jun 24, 2014 12:38 pm

Twenty bucks on Amazon:
http://www.amazon.com/BAFX-Products-TM-Infrared-Th...escription

Get one.

Tue Jun 24, 2014 12:46 pm

I have the Harbor Fright version of that infrared thermometer, but if you're measuring various areas you'll find a lot of variance. I have yet to measure the Bus motor with it, I guess it's time to use it for something besides making the puppy chase the laser!

As for the dip stick test, are we talking about the handle, or the end of the stick that is submerged in oil itself? The submerged end seems unlikely because oil at operating temp is 190° and I can't imagine a dipstick design that wouldn't allow removal by the handle with the motor at operating temperature, which is it?

Tue Jun 24, 2014 2:03 pm

Pacmanfever wrote: I have the Harbor Fright version of that infrared thermometer, but if you're measuring various areas you'll find a lot of variance. I have yet to measure the Bus motor with it, I guess it's time to use it for something besides making the puppy chase the laser!

As for the dip stick test, are we talking about the handle, or the end of the stick that is submerged in oil itself? The submerged end seems unlikely because oil at operating temp is 190° and I can't imagine a dipstick design that wouldn't allow removal by the handle with the motor at operating temperature, which is it?

I don't know where this "dip stick" test came from. Maybe in the dead of winter, when the temperature outside is 0 and you get you engine up to temp, could you comfortably pull the dip stick and not burn your hand.

A good analogy is to pull the deep stick out, place it in the oven at 180-190 degrees. Now, pick it up by the end comfortably. :D Obviously, its a metal object and the heat from the oil radiates right up it to the handle.

It's too bad VW didn't wrap the handle in plastic or non-heat transferring material, so we could check it w/out burning ourselves, especially during a hot summer day.

Tue Jun 24, 2014 2:12 pm

While I really like most of what John Muir wrote in his Compleat Idiot manual I think he may have been the one that suggested that test. I don't like it either, there is a lot a variance in temperature sensitivity between people too.