Overheating, timing . . . ?

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  • #234154
    edward ericson
    Participant

    @edsnova

    Well I put the timing light on Bridget and, for sure, she was about four degrees over-advanced.

    Looks like I had lined her up on the wrong notch last time. At 3000 RPM she was about 32 degrees in.

    Backed her off to 28, (0 at idle) and my idle went up about 200 rpm. So I adjusted that back down to 850 or so. No time to test drive tonight. Should have done all this before the trip to Auto Zone to order the new oil screen I foolishly forgot to grab in Carlisle.

    But I’ve a hunch I did some good. All the carb screws were turning the way they should to get leaner, which I’m hoping will further ameliorate my backfiring problem and maybe improve my mileage to something above the 25.5 mpg I’ve been enjoying.

    Hoping the retarded timing will make the oil pressure stay up (i.e., temperature down) during extended highway cruising, as it did before I mussed with it.

    We shall see.

    #250605
    Royal
    Participant

    @royal

    Ed, There isn’t anything that can cause static timing to change except point wear.  What distributor are you running?  Mine is their old sva.  MiGi had a 009 when I bought it.  Runs much better with the sva.  You may be in for a major tuneup:  oil, valves, points, timing, carb.  While I do believe that you were running rich, leaning out the mixture usually makes the engine run hotter.  Time for a test run. 

    #250606
    newkitman
    Participant

    @newkitman

    Ed,

    If you’re running an 009 distributor with a 34PICT3, they really don’t like working with each other. I’d switch to a SVA distributor like Roy said.

    Allen Caron
    VW based 53MGTD - "MoneyPenny"
    "If one thing matters, everything matters" - from the book The Shack

    #250607
    edward ericson
    Participant

    @edsnova

    Pertronix, Roy. SVA. The timing didn’t move; I set it wrong. Too advanced, so it ran a little warm. It did not overheat, according to my Berg dipstick thermometer. Not even close. Just lost 10 lbs of oil pressure at speed. The pressure came back after a few minutes when I slowed the car down.

    Will recheck & set the valve lash Saturday & then change the oil (VR1 20-50) and screen. Then, weather permitting, a long test drive on a hot day. Up a hill. Little over-60 highway running. She drops pressure again I’ll return to the drawing board.

    I think mainly I’ll be turning screws on the carb now, trying to get that pop and big backfire to go away.

    I’ll post & let y’all know how it goes.

    edsnova2012-05-24 22:12:55

    #250608
    edward ericson
    Participant

    @edsnova

    Well, got all that done and the verdict: not sure.

    After the oil change drove about 10 miles up a hill at about 50 mph. It’s about 85 degrees out there–was cooling off a bit from earlier. Oil pressure stayed just about even with RPMs all the way up.

    Coming back down it went a little above that. I had 30 lbs at 2800, 26 lbs at 2400, etc.

    Not really getting above 30 though after warmup.

    Didn’t have time to run her hard above 65 mph, which is where I saw trouble last week.

    #250609
    Royal
    Participant

    @royal

      Ed ??  I’m not sure that you have a problem.  If you routinely run your TD at 65+ you drive harder than I do.  Not sure how MiGi would respond to prolonged 65+ in hilly country.  Our biggest hill here is one bridge (and not a very big one),  You are concentrating, it seems, on oil pressure.  What has happened to engine oil temperature?  I noticed that engine oil temp decreased noticeably when I went from VR1 20w50 to their 10w30.  This was a rather carefully controlled test run that I made.  Curiously, since the engine was running cooler, the oil pressure was almost unchanged.   

    #250610
    Mike
    Participant

    @mike-n-scarlett

    Ed on The Samba the general consensus is as long as you maintain 10psi per 1000 rpm on a warm engine everything is ok. You seem to be doing a little better than that so i think you’re are good here. If it drops any lower than the 10psi per 1000 it may be time for a new oil pump. How was the pressure per rpm before you had the drop? What was your maximum oil temp today?

     

    180º to 210º is normal
    210º to 230º is warm
    230º to 240º is HOT
    250º is turn it off

    Mike N Scarlett2012-05-26 19:49:40

    #250611
    edward ericson
    Participant

    @edsnova

    Thanks guys.

    I don’t have an oil temp gauge. I have a Berg dipstick sensor wired to the pressure idiot light. When the green light flashes intermittently, that mean’s I’m in the 225-degree range. Solid green means 230F+ so better pull over.

    Of course, when the pressure drops below about 5-6 lbs, that same light flickers on . . .

    Anyway, I have not seen real hot temps. No green light at speed. And when I take a look at the dipstick after cruising around, the thing is pretty cool. You can see how close the sensor is to grounding just by looking–it’s just a bent wire with a thermo-coupler on it.

    So I don’t think I have too much of a heat problem. Maybe was running warm on the way up last week. I thought I was getting the oil hot enough to drop the pressure some.

    Still think that’s the case. But as you say, I’ve got to run her pretty good on the highway to see it happen. It’s not something I often do. But I would like the option.

    I’ll try again tomorrow and see if she sags.

    Roy: the VR-1 20-50 was new last summer. Seemed to do well and increase pressure slightly over the 10-40 synthetic (bought in error) that had been there, but I got it just for the ZDDP. So maybe I’ll go back to 10-40 in the fall & see how it goes.

    Thinking that now, with the carb set close to right, I’ll have less fuel in it.

    No intention of getting a new pump just yet.

    BTW, the valves were not bad. No.’s 1 and 3 exhaust were a little tight at about .004. Weirdly, No. 2 intake was loose. They’re all at .006 now.

    #250612
    Royal
    Participant

    @royal

    ZDDP.  That’s the reason that I’m using VR1.  Not that I have any opinion on ZDDP but I just read so much about it (either here or on Samba) that I figgered “couldn’t hurt” eh?  And I did go from 20-50 to 10-30 with my oil pump replacement (installed either a 26 or a 30mm -I’d have to read my old posts.  Change was easy.)  

    #250613
    edward ericson
    Participant

    @edsnova

    Yes, Looks like a $40-$50 pump and a pulley puller get it done.

    I’ll be watching the gauge.

    #250614
    Royal
    Participant

    @royal

    Ed, I adapted an old 2 jaw gear puller for the pulley.  Bought a pump puller (pretty cheap) to get the pump casing out.  You may be able to get the pump casing out without one, but I was being careful not to damage any sealing surface.  I almost installed one of those external oil filter/pump combo things but was concerned about interference with my 3487 exhaust.  Seemed like even if it wasn’t in contact with the muffler, it would be so close as to possibly heat up the oil due to radiation.  ?? 

    #250615
    edward ericson
    Participant

    @edsnova

    Yeah, I was looking at that. But I think exhaust heat from nearby pipes is going to heat everything there, whether there’s an oil filter or not. Probably best to plumb a remote cooler/filter to a spot up front, but I think of those spin-on dealies made things worse there wouldn’t be so many out there.

    Didn’t late Mexican engines all have a similar set up?

    #250616
    Marc Lipsius
    Participant

    @mrlmd

    Do you have the tin in place underneath the engine? I also put in a galvalume metal panel made from a sheet of roofing material as a firewall in front of my engine, and it runs much cooler now according to my oil temp gauge. This is the way the VW’s were originally designed and I think it works well. Plus I have the newer doghouse fan and oil cooler installed when I had my engine rebuilt. It hasn’t overheated since but I’m waiting for the hot 90+ degree weather down here. Ah, for AC. Would be nice to have in the car.
    mrlmd2012-05-27 11:21:25

    #250617
    Ed Service
    Participant

    @eddy

    How did you run the galvalume firewall on yours mrimd? I can’t seem to get mine cool enough to suit me! I live 16 miles from town and after that distance my oil temp is over 210 and my oil light is winking at me at idle! I KNOW if I can get that temp down 10 to 15 degrees the oil pressure will correct itself. I just tonight cut the holes in my spoked disc on the fake tire a lot bigger! hoping a little more airflow there will help. Machine is running perfect otherwise!

    #250618
    HappyJack
    Participant

    @happyjack

    Now that I finally got “Abby” (Fiberfab-II 1600cc dp 009 points SOLEX 34 PICT-3) out of the garage and on the road, I’m having some serious overheating problems.  Luckily,  I can now measure temp and oil pressure since I just rewired the car, adding a temp gauge and oil pressure gauge to the dash.

     It has been in the high 90’s here in coastal NC and on my 10 mile test run @ 65 mph, the oil temp went up to around 240.  I slowed down, cooled down a bit and wondered what was wrong.  Turns out that the timing was WAY advanced — over 40 degrees.  Also, the thermostat controlling the vanes in the fan shroud was stuck full up — which I believe should have opened the vanes and INCREASED the cooling???? But I pulled the thermostat and “bailing-wired” the vanes full open while I wait for a new thermostat to arrive.

    Got home, got a timing light, and reset the timing to 30 degrees @ 3000 rpm.  Also drained the oil and refilled the crankcase with VR-1 10W-30 high Zinc oil.  The old oil was a smokey-brown color…with only about 30 miles on it when the engine overheated
    Took a quick test run and so far, the oil temp is holding at about 180, but it was also a lot cooler today.   So more fine tuning of the timing as well as more test runs once it warms back up to 95 degrees should tell me if just adjusting the timing and messing with the thermostat gets me into a safe temp range on this car.  Hope I did not overheat and damage the engine.  
    Seems I have a lot to learn about air-cooled engines and North Carolina summers…and carbs and distributers and timing, and…

    Happy Jack
    "EMMA" Red BCW TDr on 1971 VW w/ rebuilt 1641cc
    Dual Kadron, mild street SCAT cam and lifters Hide away exhaust and headers
    "MANYPENNY" White CMC TDr '78 Ford Pinto components w/ 1988 Mustang II 4 cyl w/ Weber

    #250619
    Ed Service
    Participant

    @eddy

    Yes, thermostat full up is vanes open, should be maximum cooling.  I have been a mechanic for over 40 years and I’ve learnt more this past couple of months than I ever thought possible! but I still can’t get this darn VW to cool down! I know vmy engine isn’t in new condition but it has good compression and is clean with no oil leaks. It wouldn’t concern me so much if the oil light didn’t come on, NO mechanic likes looking at a red light!   It never comes on until the oil gets above 210 degrees   

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