popping from carb

Glad to hear that one is solved!
Art

My mechanic friend came over again tonight and we took a look in the distributor. We compared the old points to the new ones. The spring on the old points was significantly stouter than the one on the new points. I checked the kit after searching the forum and seeing a similar post about the weaker spring floating the points above 2000rpm and did not find another spring or a helper spring. After re-installing the old points the boat purrs like a kitten and revs like it should. Thanks again for everything. Its such a beneficial tool to have advice from experience at my fingertips. Needless to say I have ordered a new set of points with a stronger spring.

The coil on the vw is red in color. I have a test light and voltmeter. What is a good bench test for a coil? Or is it ok the throw the vw one on it and try that? I will be able to run the boat tonight and unhook the choke wires.

I'm still concerned that the choke heater might be hooked up to the wrong side of the resistor. Run the engine and after it's warmed up, unplug the positive wire off the choke housing and see whether the engine behaves normally.

Unplugging the wire will take the choke's load off of the ignition system and raise the voltage some.

Whatever coil you try needs to be a non-internal resistor type coil. Some have resistors in them. Don't know anything about VWs.   
Art

mcfunnymoney wrote: It will spin up to 2k then bog and not go any further. It sounds like its running out of power (electricity) It seems to be advancing with a timing light. The springs are unbroken and recently have been cleaned and oiled. Weak coil? Bad resister? I set the points at .018 when they were new two weeks ago. New cap, rotor, condenser.

If you changed all that you had the plug wires off.. check the firing order, then check it again.

If you have low voltage to the coil (would need to check it under load) you could experience similar symtoms as well.

A great big ignition wire bypassing the switch and going straight to the battery would be a decent test

I have a vw bug. I can steal that one and give it a shot

It will spin up to 2k then bog and not go any further. It sounds like its running out of power (electricity) It seems to be advancing with a timing light. The springs are unbroken and recently have been cleaned and oiled. Weak coil? Bad resister? I set the points at .018 when they were new two weeks ago. New cap, rotor, condenser.

Well I have an admission. When I rebuilt the carb I used the wrong gasket between the base plate and the body. I will definitely never do that again. It stinks being wrong or making a mistake but it Im happy that I finally figured it out. Good sleep tonight. Thank you for all of the help and ideas. The boat idles great and starts great also. I hate to admit it but there is one more problem. It wont rev past 2k rpms. when I punch it the tack drops to 1k and it bogs. When loaded the carb secondaries dump as they should etc. My mechanic friend had to leave before much digging last night but he was fairly confident I had a weak spark or it was weakening with rpm's . I'm happy to start a new thread if necessary. I don't know the format here. Again, thank you guys so much for everything so far. The boat thanks you too!

Marine carbs don't have a fast idle cam like auto carbs do. Fast idle is accomplished with the throttle.

Hope that your wife has her tongue planted firmly in her cheek when she says that. It's never good when they are serious about critisizing our boats!

Ask your mechanic friend to go over the coil/resistor/choke wiring. If the choke is wired to the coil side of the resistor, it will pull the voltage so low that it might affect the performance of the coil.

Art

Holley choke cap and gasket part# 45-258.



Advance Auto Parts

Is the 4v on the "other side" of the resistor with the points open, or closed? If it's points closed, it's probably OK. It should go to a bit under battery voltage when the points are open.

A malfunctioning choke will have no effect whatsoever on engine vacuum. Once the engine warms up, the choke is out of the picture anyway. Of course the vacuum will still be applied to the housing. I guess they do that to keep the choke from overheating.   

I don't think there is any opening into the choke housing other than the vacuum port. If the gasket is good, there should be no airflow into the choke housing, and therefore the engine won't get extra air via the choke. Could it be that the housing gasket was failed to begin with? If there is a speed shop (hot-rod shop) in your town, you might be able to buy that gasket as a separate item there.

Let's test the choke heating coil off the engine. Just run 12v and ground with small jumper wires to the terminals on the cover. Watch the "coil" in there for at least two minutes and see whether it starts to move. You might have to put a clear glass dish or something similar over the open side of the choke housing to retain the heat. If you leave it completely open it might lose enough heat to keep it from operating properly.

The purple wire on the choke housing comes from the ignition switch, via the "high" side of the resistor. Here is what the circuit looks like: Starting from the terminal on the starter relay where the red battery cable connects, battery current flows from there to the ammeter, then through the ammeter. (<Your boat does have an ammeter in it as opposed to a voltmeter, right?>) From there, a red wire goes from the ammeter to the "hot" side of the ignition switch. When you turn the switch to "on," the red wire is connected to the purple wire coming out of the ignition switch. From there, it lands on the "high" side of the resistor, where the wire to the choke stove also is connnected.

Now, all of the wire mentioned above will cause a certain amount of voltage loss. There are two occasions when ignition current has to pass through the 8-prong plug at the right rear corner of the engine where the engine harness plugs into the boat harness. Unplug that plug (it might be taped up. Take off the tape.) Get some fine sandpaper and clean up the prongs on the male side of the plug. Then roll up a little piece of sandpaper and clean the holes on the other side. Use an in-and-out motion to sand the inside of them. It is very common for those prongs and receptacles to have corrosion on them, resulting in a voltage loss.

If voltage loss is causing your ignition system to have weak spark, you can try this: Run a small jumper wire from the "high" side of the resistor to a source of 12v. (the engine end of the + battery cable is good. It's on the starter relay, remember?) BE CAREFUL that you don't hit anything grounded with the jumper while is't connected! You don't want to be welding! Start the engine with that jumper in place. REMEMBER that with the jumper in place you won't be able to turn the engine off with the ignition switch. You will have to have the switch off AND the jumper disconnected.

I didn't get a chance to have a look at a carburetor today. Hopefully tomorrow!    

the choke is getting 9v with the points closed and 10 volts with them open. the coil is getting the same voltage. annoyingly the other side of the resister is only getting 4v. So it appears that the choke is hooked to the correct side of the resister. The batt has 12+ volts. Im wondering of the choke has not worked in awhile. The main issue I have is the vacuum loss mystery. Could a malfunctioning or low voltage choke cause a vacuum leak? Also unfortunately I messed up the gasket on the choke so I at least have to buy a cap. Where does the red wire originate that goes into the harness loom on the top of the engine?

I did note that the tang was around the coil so thats step one... I will try the operation of it this afternoon. I checked the voltage the other day and it was only 9v. The battery might be low though due to cranking. (although it did turn the engine at a normal speed) I will charge it tonight and check again tomorrow.

Sorry. I should have said that. Yes it is electric. The wires get a key on voltage. I haven't seen it work properly (move the butterfly) to date but it was lower on the nitpick list than the boat running so I had overlooked that. I took the cap off of the choke housing and it looked pretty clean inside there and the piston moves easily. I haven't messed with an electric choke before so any help would be great. I found a replacement cap at the parts store but they aren't as cheap as I was expecting so I hate to buy one if I possibly don't need to.