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Full Version: All 4 cyl cooling fans have same TDC mark?
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clubracr
Is the TDC timing mark in the same place on 4 cylinder cooling fans regardless of displacement?
tat2dphreak
IIRC 1.8 is different, 1.7 and 2.0 is same.
SLITS
And don't take the TDC mark for true.....some are about 15 degrees off from the flywheel mark........

1.8 should have TDC and 7.5 degree marks
1.7 / 2.0 should have TDC and 27 degree marks

Unless it's new and it will only have a TDC mark (maybe).
URY914
QUOTE (SLITS @ Aug 17 2005, 11:57 AM)
And don't take the TDC mark for true.....some are about 15 degrees off from the flywheel mark........


Is the flywheel mark always the same?
Cap'n Krusty
Bus fans have the mark in a different place because the scale for timing them is in a different place. TDC is TDC, however, so ALL the 914 fans should be marked the same. Timing marks vary because timing specs vary. 1.8s are timed differently than 1.7 and 2 litre engines. Flywheels that are marked should all be the same. The Ca[p'n
clubracr
I'll explain my dilemma and go from there. My race engine is based on a 1.8. My cooling fan is off of an unknown engine size. It's cut down, lightened, no belt ring, etc. My flywheel has been machined and balanced down to 7 lbs. so there is nothing but ring gear showing. No timing marks there. I'm having problems with the engine not wanting to rev quickly or smoothly, especially under load(driving in gear). It does rev better sitting in neutral but still it feels like there is a boat anchor tied to the crankshaft. It has duall Dell 40s, an 050 dizzy w/ Pertronix, and I've timed it at 32 degrees @ 3000 rpm with a dial-in advance timing light. It also wanted to overheat on the pace lap so I brought it in. Valves are set to what the engine builder told me to set them (.004, .006) Engine has about 10.5:1 comprression if that matters. I'll provide any info anyone requests and answer any questions. I'm ready to pull my hair out over this car.
clubracr
BTW-I really only need to know if the TDC marks are all the same. I can dial in advance with the timing light.
Brian Mifsud
My '76 2.0 only had one (white scribed line) mark on the impeller. I interpreted that as TDC (at least for purposes of valve adjustment).

I noticed a little crank-mounted pulley that sits behind the fan (and isn't used for anything). Is the notch in that pulley TDC or what?
tat2dphreak
QUOTE (Brian Mifsud @ Aug 17 2005, 05:54 PM)
I noticed a little crank-mounted pulley that sits behind the fan (and isn't used for anything). Is the notch in that pulley TDC or what?

huh.gif you mean the one for the altenator?

or did the car have an A/C?
Brian Mifsud
AC it must be! The engine isn't original to my car, and mine never had AC, but I guess that makes sense that it an AC adapter pulley. What a pig a '75/'76 California car must have been with Smog Airpump sapping power on the same power takeoff as the alternator AND AC. Not much left to move the car around..
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