71 Bus overheating and shutting down - need help...

[Wildthings]

[AlohaMyFriend]

I'm looking to install an oil temperature gauge so hopefully I'll never fry my engine.
Can anyone recommend one and the sensor, preferably with a link?
Thanks for all your help.

[bsairhead]

If your worrying about frying your engine, get a CHT gauge. An oil temp gauge is good for trending. Your oil temp can be under 200 and your cylinder temp can be above 400.

[AlohaMyFriend]

Thanks for your response.
So installing the CHT gauge seems crucial if I never want to overheat & blow my engine, correct?
This gauge seems to be the right one: http://www.ebay.com/itm/330737576666?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649

[Wildthings]

You don't mention what kind of engine your are running, but with a T1 loosing a fan belt is a good way to kill and engine. The charge light will tell you if something is wrong with the belt, but beyond that some kind of light that comes on if and when the heads get too hot would be the best for saving your engine from a sudden failure. Gauges while great for tuning are all to easy to ignore.

[Desertbusman]

CHT gauges are essential on late bus T-4 engines. But very very few people ever put them on a T-1 like yours. Different engines and the failures are quite a bit different.
But about everyone would recommend you put on a oil temp and oil pressure gauge. Granted, a temp gauge is not going to give you the real oil temperature and you use it mainly for trending. Now an oil pressure gauge will be a great, and a better indicator of oil and general engine temperature. Hot engine>hot oil>decrease in oil viscosity>drop in pressure. Since oil pressure also varies with engine speed you will soon get usesd to what the pressure normally is at differnt speeds. Then a fluction of that normal is your overall engine temperature monitoring. I think everyone considers the pressure gauge as the very most important.

If you really want to know more about the actual oil temp here is a good inexpensive way. A meat thermometer to stick down the dipsstick tube. Not used permanently but good for comparing gauge readings with actual oil temps.


Another thing, if you do get an oil temp gauge never compare it with any one elses gauge readings. Different sender installations vary the gauge reading drastically. So just use it for trending on your engine only. Same thing holds true when other people tell you what is a good, safe, or bad gauge reading. Actual accurate oil temp is one thing, gauge readings are something totally different.
_________________
The best thing that anyone can do for their Bay is get the Volkswagen of America Official Service Manual published by Robert Bentley. Without it the bus is pretty much doomed.

[bugnut68]

[RatCamper]

I don't think the blocked off heater pipes are a major disaster in process. May I ask first if the heater system was the same before you had it worked on?

How did you determine how much the fan was blowing?

What concerns me is you said you had the fan changed. You meant fan belt, right?

Are you absolutely sure the generator belt is still tensioned correctly. It takes a lot of energy to spin that fan fast enough, especially at higher RPMs so if the fan belt isn't tight enough the belt will slip more and cooling power will be severely impacted.

Yes there are a few things I see on that engine that shouldn't be but the fact that it's only manifesting after a tune up of sorts says there is another new factor at play too.

The hesitation on takeoff could be timing or even some kind of fuel starvation / over lean condition. That would cause the engine to get hot.

Somebody help me out on this next one please. I'm having a bit of a bad brain day. I remember that when timing is adjusted too far one way the engine sounds loud and chuggy and the other way it sounds really smooth. I'd like to say loud and chuggy is retarded and smooth is advanced but I'm doubting myself a little.
Either way retarded or advanced timing can cause overheating for their own reasons.
_________________
Vehicle: 1975 Special order delivery walkthrough panel based pop-top camper (LCA / Sunliner). Motor: Nippon 1.8L Single port Wasserboxer, Transmission: 3 rib 002.

[Wildthings]

[Desertbusman]

Comments from the beginning where you first posted-

-Carb running clean? You must mean if it's working well and you have a good air/fuel mixture. Is it correctly adjusted per the book? Do you have the service manual? If not then get one now and adjust the carb per the book. You said you are going to put in new plugs so do that now. And then you can find out about your air/fuel mixture by "reading" the plugs. You will have to dig up the info on how to do that. But it will tell you if you are lean or rich. Lean causes greater engine heat.

-Yes, do the oil to the line. For SoCal Whittier I'd recommend that you use 10W-40 year around. 20W-50 would be decent for summer only.

-Lay a drop light on the ground under the bus at night. When looking in the engine compartment anywhere you see light needs to be sealed. Holes in rear tin, new seals, etc.

-I'd slow down the timing a tad from the 32*. I run mine at 29*. With your mechanical advance only distributor (probably a 009) you set it at max advance which for yours will be max at least by 3,000 rpm (actually around 2,500). The thing is you don't set it at idle. But check it at idle to make sure it does give advance action. If your electronic module is a Pertronix then that is a great thing for performance and cooler running.
-Without going into a big discussion the big potential for timing problems is your stock steel crank pulley. I'd highly advise you get an aftermarket aluminum degreed pulley. $30 will do it. Then you can do the timing accurately.

-Oil burning smell? Naturally, with all the oil coating and dripping. Take the effort to get that sucker clean. If you don't have some ramps take a couple wood blocks to drive up on at the local DIY coin op car wash. Use aerosol degreaser and lots of soap suds. Let the engine cool down before using the degreaser per the directions. A cheap home pressure washer is really handy. At some point you will want to pull down the tins under the cylinders to clean it better.

-He did the valves but you should at least recheck them. .006" cold engine.

-Looking at the picture, you have a fuel filter before and after the fuel pump. Get rid of the one after as it might lead to problems. Now the fuel line is right near the intake manifold heat riser. Very good way to totally burn and destroy the bus. However you have headers. some headers have port connections to the heat risers and some don't. And some port connections are blocked off. Check yours. If the heat risers get real hot then they are connected. that's a topic not needing big discussion now except for your potential fuel hose fire.

-Now to the topic of the plugged fresh air outlets on the fan shroud. Don't get shook up thinking it will fry your engine. But there are considerations. Heat exchangers when turned off are intended to have a small amount of cooling air flowing thru them as controlled by the dual purpose HE flapper valve. Also a stock muffler has restrictor holes in it's preheat pods. You don't have a stock muffler but rather a header without the pods. Bottom line is if you conect fresh air hoses directly to the HE's you will be robbing a lot of cooling air that should be going to the cylinders and heads. If you replace the HE's with J tubes ($15) then you can leave the fan shroud holes plugged and retain that cooling air for the cylinders and heads. J tube drawbacks are no more winter cabin heat and also J tubes radiate unwanted heat to the heads. Almost as much as uncooled HE's. There are simple deflectors you can make and clamp to the J tubes to eliminate that problem.
I've gone back and forth between J tubes and HE's on both my dubs. Currently have HE's on the bus with fresh air hoses directly connected to them because of also running a header. But also have shroud plugs like you but with a 1/2" hole drilled in them to limit wasted air. It's a tradeoff. For the sake of the engine and not my winter comfort I like J tubes better.
Most of next week is forcast for 111* and my dubs get pushed hard in 115-118* so best utilization of the fan shroud cooling air is a big deal.

-Like mentioned before at least get a oil pressure gauge.
_________________
The best thing that anyone can do for their Bay is get the Volkswagen of America Official Service Manual published by Robert Bentley. Without it the bus is pretty much doomed.

[AlohaMyFriend]

Alright. So I will get an oil pressure gauge, as that seems the most important.
The fan was replaced due to cracking in the center. (My 1st engine fried due to a messed up fan also, hence why I want to prevent that from ever happening again.)
I don't think I have a fuel filter after the fuel pump but if I do then I'll remove it.
I take it I should use J tubes with deflectors to eliminate heat to the cylinders and heads.
How do you suggest I place the fuel line so it's not near the intake manifold heat riser?
Thanks for your help.

[ccpalmer]

[Desertbusman]

[aryue]

The incoming fuel line from the front firewall tin to the pump is supposed to be a metal line, part # 113-127-521A.

http://www.wolfsburgwest.com/cart/DetailsList.cfm?ID=113127521A

Also, get the grommet that goes into the firewall tin, along with the plastic plug wire holder that clips into the fan shroud to retain both the fuel line and #3/4 plug wires.

http://www.wolfsburgwest.com/cart/DetailsList.cfm?ID=111127591

The plastic plug wire holder that has a spot for the fuel line can be difficult to fine.

http://www.wolfsburgwest.com/cart/DetailsList.cfm?ID=113905451B

- Andrew in Austin, TX -
_________________
OldandSlow - but still chuggin.
http://www.ph.utexas.edu/~yue/VW/VWBus.html

[Desertbusman]

BTW, for around the SoCal metopolus and trips out to the deserts and mountains you might also consider a deep sump. Mine couldn't survive with out the cooling and added oil capacity they provide.
_________________
The best thing that anyone can do for their Bay is get the Volkswagen of America Official Service Manual published by Robert Bentley. Without it the bus is pretty much doomed.

[bugnut68]

[bugnut68]

[Wildthings]

[bugnut68]

http://www.thesamba.com/vw/forum/viewtopic.php?t=434051&highlight=heater+boxes+hoses

Specifically, point number nine:
9) The heat exchangers serve two purposes. First, obviously, they provide a source of heat for the occupants. Secondly, they remove excess heat from the cylinder head. Heat always travels to cooler surfaces, so it travels from the hot cylinder head, to the cooler exhaust pipe, the cooler fins (heat sink), to the cooler air that is passing over them. Many people don't know that the heat exchanger is operating all the time when the engine is running, regardless of the position of the heat control lever in the car. The lever in the car controls a diverter valve internal to the heat exchanger (another flap) via a cable that runs from the lever to the arm on the side of the heat exchanger. This valve directs air flow into the hose that leads to the heater channel when the heat is "on". When the heat is off, the valve closes the port that enters the car and opens a port on the top of the exchanger, toward the front. With the heat off, the fresh air tubes still deliver air to the exchanger to transfer excess heat from the cylinder head. This heat is then expelled through the top port on the exchanger and exits below the engine compartment. For this reason, even I you don't care to use the heater, if you still have heat exchangers, you should always have the fresh air tubes connected.

Nuff said.

[bugnut68]