engine and drivetrain Carb Question - Weber 32/36

[davej]

Let me start off by saying I know zip about the black magic that is a carburetor, so you can't dumb down your answers enough. =) 

 

Problem/Background - car started stalling out, sometimes at low idle, sometimes at 70mph on the highway the engine will just cut out. it usually starts right back up and i can continue on my merry way. (usually)

 

Tuesday it died on the way home and wouldn't fire up at all, i swapped in a clear cheap-o fuel filter and it wasn't filling up, took the fuel pump off and it seemed to have suction when i would push the spring, but didn't see any way to get further into it than that, so i clean it up a bit, put it back on and the car starts right up. runs fine for a few days, but had trouble starting/staying running for more than a few seconds at lunch today.

 

I took off the air filter to find a bunch of liquid/goo on the filter tray. Anyone know what that is or what caused it to get in there? is that oil? there's a vacuum hose from my valve cover to the carb, so i'm assuming it's being drawn into the carb from that but can anyone explain to me like i'm 5 what that's for? (or have a link to a good site for an overview?)

 

Other work I've done, replaced the fuel sending unit in the tank about 4 months ago because previous one's wires for level sensor were broke. the screen on the working one still looks good, no clogs or anything. 

 

I use 93 but it has the corn syrup in it, the longest the car has sat is about 10 days over Christmas with out being driven, so i'm not sure if that's long enough for the ethanol to gum up stuff?

 

If there's more photos/angels i can take to help just let me know. 

 

some guys at work were saying i should probably rebuild the carb, found this kit 

http://www.piercemanifolds.com/product_p/92.3237.05%20major.htm

from this thread http://www.bmw2002faq.com/topic/140194-weber-dgav-rebuild/

 

 

 

 

overall engine shots

 

Also, initally I wasn't sure if i was missing spark or fuel, although leaning toward fuel, here's some photos of my distributor in case something looks out of place to anyone. 

 

[GreenSwede]

The oil in the air filter probably indicates that the engine is worn, in sweden we say crank house compression. The compression passes the pistons due to worn rings/cylinders and causes pressure in the crank house which goes up and presses the oil out the ventilation hose from the valve cover - ending up in the air filter. Mine did that a lot before I rebuilt the engine. The goo looks a little like you´ve got some water contamining the oil. Long time since you changed the oil?

 

That shouldn´t have anything to with the car cutting off, though. I probably soots your plugs a bit, which could be a pain. Before I rebuilt the engine I plugged the hole in the air cleaner and installed a separate filter for the crank house ventilation, on a hose with a 90 degree bend upwards an then a bit of length, so as much as possible would flow back into the engine. But mostly to save the plugs from the excessive oil.

The other things sounds carb related to me. Maybe a good cleaning of the carb would do the trick, or a rebuild.

Edited January 16, 2014 by GreenSwede

[Hans]

I'd look at fuel feed problems first. Its conceivable that something is floating around in the fuel float bowl that temporarily blocks a jet, but the empty filter is perhaps a hint of a leak or poor pump. Make sure all the clamps are tight, pull the trunk panel and check connections -  there should be a plastic spacer on the outlet pipe. You may also have grunge floating in the tank that blocks then releases on strainer. Then perhaps pull top of carb and see what's in the bowl. And yes, you have a blow-by problem that indicates warn piston rings, etc.

[peterschop]

I see you don"t have a fan on the front of the engine. Do you have an electric pusher fan? If not, does your engine overheat?

[Hans]

Good eye. You need a fan. Also, is that oil around base of dist cap? If so, pull rotor and plastic cover....any oil on points? Also, clean grease off rotor contact snd inside cap. Cap terminals look like they could be cleaned.

They say....that most carb problems are electrical. May be true here.

[182kartracer]

I would go ahead and buy a carb rebuild kit. They are 30 bucks and are easy to do in a night or two. I noticed a significant improvement after i rebuilt mine. Even if that isn't the reason for your issue it's still money well spent.

[davej]

Thanks everyone for the replies so far.  Any idea how long an engine is good for after a refresh? (i realize answers are pretty subjective to conditions) this car had a bmw certified re-manufactured engine put in 42,000 miles ago, (but that was also 16 years ago) so i'm hoping it was at least a solid baseline to begin with. 

 

GreenSwede, thank you for your explanation of what's going on under the cover, it was very helpful! 

 

I'd look at fuel feed problems first. Its conceivable that something is floating around in the fuel float bowl that temporarily blocks a jet, but the empty filter is perhaps a hint of a leak or poor pump. Make sure all the clamps are tight, pull the trunk panel and check connections -  there should be a plastic spacer on the outlet pipe. You may also have grunge floating in the tank that blocks then releases on strainer. Then perhaps pull top of carb and see what's in the bowl. And yes, you have a blow-by problem that indicates warn piston rings, etc.

 

Hans, clamps seem good all around, i do have the plastic piece at on the fuel sender in the tank. The line in the trunk is the old cloth covered one, which is probably original and needs to be swapped. I did notice the fuel pump does not have gaskets around it, not sure if that could contribute to air in the system, but they are on order. (is there a way to service the pump? or do people just get a new one? i have #13 31 1 265 192) Any tricks to cleaning grunge out a gas tank? (other than a complete removal?) 

 

I see you don"t have a fan on the front of the engine. Do you have an electric pusher fan? If not, does your engine overheat?

 

I love this community, nothing gets by you guys! yes, the previous owner had installed an electric fan on the other side of the radiator. (which i think is one of the 320 rads.) he also installed a really nice digital oil pressure and temp gauge in the car, it might actually be running a bit cool, 165-168f is about avg now, and 172-175 in the summer. 

 

Good eye. You need a fan. Also, is that oil around base of dist cap? If so, pull rotor and plastic cover....any oil on points? Also, clean grease off rotor contact snd inside cap. Cap terminals look like they could be cleaned.
They say....that most carb problems are electrical. May be true here.

 

it was some sort of oil/grease on the dist cap, what's the best way to clean up those parts? just wipe them down? I'll pull the rotor/cover and check the points; which is another black hole for me, the PO changed the points out at 37xxx miles, about 5k ago. i've been reading about doing that but still don't have a confidence level to tackle that. do the points continue to play a roll in the ignition process while the car is running, or just when you're trying to start it up?

 

I would go ahead and buy a carb rebuild kit. They are 30 bucks and are easy to do in a night or two. I noticed a significant improvement after i rebuilt mine. Even if that isn't the reason for your issue it's still money well spent.

 

major rebuild kit was shipped from Pierce yesterday, time to jump in the deep end and see if i can swim.  =)

 

 

one other question, as i was reading up more on blow-by, there were a bunch of posts on the interwebs from people saying they used products like Restore Engine Restorer, and also adding Sea Foam to a tank of gas to help clean out jets and such. I'm curious if anyone has used products like that, good or bad experiences? part of me reads the description and thinks....Snake Oil, but maybe not. 

 

thanks!

[Hans]

Get a can of Brake-Klean and carb cleaner from the auto supply store, along with some fine emery paper. Best to wear eye protection when spraying any of these things. Spray out the cap, clean off the rotor top and use emery paper (a form of sandpaper) to clean the four contact posts in the cap and the rotor contacts. For now, just pull the plastic cover and see if there is any oil in there. there should not be oil on the cap. Might as well check plugs - they may be oil-fouled.

 

The points are fundamental to the engine running. If out of adjustment, car will run poorly. You can search the forum for instructions on checking/replacing and setting them but I strongly suggest you order Haynes manual (check FAQ supporting firms) with express delivery. It will pay for itself. There are excellent You-tube videos available on rebuilding carb. Watch those first.

 

The fact that your cars runs OK but acts up intermittently would not immediately have me rebuilding the carb (cleaning in situ, yes), but it won't do any harm. I'd look in the fuel tank again for corn sludge, and check all fuel line clamps, hoses. But first the ignition system.

[peterschop]

If it were my car, I wouldn't touch the carburetor until I gave it a full tune up. As they say, 90% of carburetor problems are ignition. If your car is not in good tune, you will never correct the problem with your carburetor.

 

Lets start with the goo in your air filter tray. It looks like blow by sucked in from the valve cover. That hose is provided to relieve pressure from the top end of the engine. Excessive oil would indicate a worn engine such as bad rings. It also helps relieving moisture build up in your engine. All that goo coming out of the engine is sucked down your carburetor and into the engine to be burned off instead of being vented into the atmosphere for us to breathe. With that being said, most of our old cars by now have been modified to not suck that goo through our engines. On my car there is a small filter on the side of the valve cover to catch some of the oil before venting to the atmosphere. A better way would be to direct it to a catch can that can be cleaned out occasionally.

 

You mentioned your coolant temperature. It sounds a little low to me. It could be your engine is not warming up enough to evaporate any condensation in your engine, therefore contributing to the goo build up. Is your thermostat working properly? It should close off the radiator until the engine temperature needs to be brought down. If the thermostat does not close all the way, it may never fully warm up and burn off moisture. Or maybe a warmer thermostat is in order.  

 

To see where that moisture is coming from, I would have my oil tested to see if there is water in the oil. I use Blackstone Labs to analyse my oil. They will send you a kit to take an oil sample when you change your oil. For about twenty bucks they will show everything in the oil which may help determine the condition of your engine. BTW NFI.

 

When was the last time you checked the plugs and points or adjusted the valves? That goo may have fouled your plugs. Points wear and need to be checked. Valves wear and need to be adjusted. These cars are not like modern cars that can be driven 100K miles without a tune up.

 

As far as the ethanol in the gas, it will not gum up anything in ten days. I fill my car in the fall before putting it away for the winter and it always starts in the spring with no additives.

 

Also you mentioned your fuel filter was not filling up. It will not fill all the way. You should see fuel in the bottom half but you will have a bubble in the top. 

 

 

[peterschop]

I forgot to add that your points have every thing to do with your engine running. They are the trigger that tells you coil to send spark to your spark plugs every time they fire.

[davej]

Thanks Hans & Peter, 

I was looking around for what an old school tune up includes and found this linked in another post here. 

http://www.02restoration.com/restoration-tips/maintenance/basic-tune-up-procedures/

I don't have the tools it asks for (but that's a great excuse to get some) but would there be anything else you guys would include in a tune-up? (besides changing the plugs also)  some other threads suggested Bosch W8DC plugs, but I can only seem to find WR8DC+ think that would make a big difference?

 

Peter, I'll check the current plugs tonight and see if they are oily. As for valve adjustment, the PO performed one about 5k miles ago, but i have zero idea what it entails to do it myself. 

 

 

These cars are not like modern cars that can be driven 100K miles without a tune up.

 

 I'm finding that to be true! This has been a great crash course for me in basic mechanics, hopefully things will continue to make sense and my learning mistakes won't be too costly. =)

[Hans]

you should get the Haynes manual for the car. Maybe $20. It explains the basics and specifics of your car, step by step. For tools, feeler gauges, timing light with automatic advance setting, metric wrenches and sockets; try Harbor Freight - either in person or on-line.

45K isn't much for reconditioned motor, but maybe it needs to run more to loosen up the rings if it was sitting. I'm not a big fan of secret formula additives, but many are, so make your own decision on that one. I'd look in the tank and see if its clear. If there is sludge, you'll need to remove and clean.

[Buckeye]

 As for valve adjustment, the PO performed one about 5k miles ago, but i have zero idea what it entails to do

Here is procedure out of book for valve adjustment.

http://www.bmw2002faq.com/index.php?app=core&module=attach&section=attach&attach_id=66240

[peterschop]

First thing you should do is pick up a manual on the car. "Haynes 1602 & 2002 Owners Workshop Manual" is a good one to start with. You can pick up a used one on Amazon for ten bucks or maybe find one on this site. Or find the BMW factory blue book set but you will spend more like $150 for that. Haynes will give you all the info you need and more.

 

The second thing is get to know the search function of this site. Tons of useful information. You can start with what spark plugs to use.

 

A 2002 is a hands on car that needs to be checked on often to keep in good running condition. Not hard to work on but you will need basic tools and yes, a good excuse to buy them. See if you can find other 2002 owners in your area and maybe find someone who can help adjust valves, points and timing. Half the fun of the car it tinkering with it and the friends you make.

 

BMW calls for a valve adjustment every 10,000 miles but it wouldn't hurt to do it after 5K. They also call for the plugs to be cleaned and gaped and the points adjusted after 5,000. Don't forget, anytime you adjust the points, you have to check the timing.

[davej]

Thanks guys, book on order. 

 

stopped at napa on the way home and they had points for the car, so picked one up. (didn't have a condenser in stock though)

 

here's a photo of how it looked when i took the dust cover off. 

 

read i could put the car in 5th gear and rock it back and forth to advance the dist. shaft, so tried that. Does this look like it's lined up right? shouldn't there be a gap at that connection in this position? 

 

 

Another shot of the alignment 

 

and here are the points napa gave me vs the one in the car now. it seems the part that connects to the shaft is smaller on the napa piece, does that matter? 

 

 

Should i try to adjust the points in the car currently, or can you tell they are no good? any tips on how to actually adjust these? do you just bend the connector that's not on the moving arm away to whatever the proper gap is when it's on the corner of the shaft?

probably all of these answers and more will be in that book, but thanks for any life experience you can share.

 

oh, and here's a picture of the ignition coil (i think) for good measure. 

 

here's what the plugs looked like

#1

 

#2

 

#3

 

#4 - had some oil around the base of the threads

second shot of #4

Edited January 18, 2014 by davej