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> Help - need engine advice, Fan Pulley has play in it
tabwb
post Mar 29 2023, 03:38 PM
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So, I think it's time to go to the well and throw this dilemma out to the masses. I'll cut to the chase - my 1976 had a 1.7 engine in it when I bought the car. I knew that it wasn't the right engine so my nephew and I rebuilt a 2.0 engine he had picked up. We picked up the necessary rebuild kits from 914 rubber, auto atlanta, pelican, etc. - all new stuff on the inside. Block sent out, machined where applicable, etc. Dropped the 1.7, put in the 2.0 - all good so far. We put about 700 miles on the car with the 2.0 and recently, during a short drive, he heard a "funny" noise. Upon inspection I noticed that the "fan assembly" had some play in it - that is, the pulley itself was able to be wiggled about 1/8 to 1/4 inches fore to aft (horizontally). The pulley bolts are tight, no issue there...it's that the driveshaft (pulley to crank to flywheel) has a front-to-back play the distance noted. Now, I will drop the engine and trans...but what are the chances that engine-internals are damaged (bearings, pistons, rings, etc.)? I'd love to get away with just a few spacers on the back end, reset the flywheel and put it all back together and load it back in but am I just asking for trouble? Is it worth the risk or am I looking at another complete rebuild?

Any advise at all would be helpful and thanks in advance - you folks have saved me before.

WB
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mgphoto
post Mar 29 2023, 04:06 PM
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The fan hub center bolt could be loose, that should create an oil leak at the seal, or loose flywheel to crank bolts, this could cause major damage.

1/4 inch movement is .250”! That is huge axial play should be.0028 to .0051”
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930cabman
post Mar 29 2023, 05:56 PM
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My $5. would think the hub is loose on the taper. Do not run this until you find the culprit. Good luck
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r_towle
post Mar 29 2023, 06:16 PM
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Remove the fan
Is there the correct washer behind the fan, check to see if it’s there.
Tap crankshaft while measuring endplay at the flywheel, see if that is correct.

Rich
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technicalninja
post Mar 29 2023, 08:33 PM
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Before I dropped the engine, I would verify that the movement felt at the pully could also be felt in the flywheel access hole.

.250 is a bunch!


What was crank endplay during your build?
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ClayPerrine
post Mar 30 2023, 06:02 AM
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QUOTE(technicalninja @ Mar 29 2023, 09:33 PM) *

Before I dropped the engine, I would verify that the movement felt at the pully could also be felt in the flywheel access hole.

.250 is a bunch!


What was crank endplay during your build?


(IMG:style_emoticons/default/agree.gif)


This sounds like the crankshaft end play is not set correctly.

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technicalninja
post Mar 30 2023, 09:21 AM
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The real question from the OP is "should I tear it down for inspection?"

We are all real good at giving advice on how to check and what to look for but no-one has answered the direct question yet.

I asked about differences in 1.8 and 2.0 gasket sets and had 6 suggestions before DaveP answered my root question...

The answer that the OP is looking for from my perspective.

If, the thrust play was across the entire crank and the front pully is not loose.
And, I had hit my thrust target of .004 during the build...

I'd be a HONKED DONKEY!
It would come ALL the way down as the only thing that might cause that is complete destruction of the thrust flanges on the main bearing.

Lots of other engines have separated thrust bearing that can fall out if clearances were not correct. The Type 4 is built on to the main bearing and cannot drop out like a Mazda NB and most of the Toyota stuff.

No way I'd try to cheap shit that if I really had thrust clearances the OP described.
It might be cheap to fix now.
Have it come apart at speed and you might be looking for the entire engine...
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technicalninja
post Mar 30 2023, 09:23 AM
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Loose front pully OR loose flywheel might also cause this as well.
Both would be builder error.
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brubou
post Mar 30 2023, 10:44 AM
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I got $9.14 on it being the fan hub!! Let’s go big bucks, big bucks, no whammies…
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tabwb
post Mar 30 2023, 12:55 PM
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QUOTE(mgphoto @ Mar 29 2023, 06:06 PM) *

The fan hub center bolt could be loose, that should create an oil leak at the seal, or loose flywheel to crank bolts, this could cause major damage.

1/4 inch movement is .250”! That is huge axial play should be.0028 to .0051”


Thank you so much for your information...I will check that.
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tabwb
post Mar 30 2023, 01:01 PM
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Thanks all for checking in and advising me. I'm kinda leaning towards "build error" (my first one) and it sounds like I need to err on the side of caution and maybe do a full, new rebuild -- just in case. But, first I will check the items identified by the various responses - do the easy stuff first and go from there.

I'm living and learning!

You guys/folks never cease to amaze me!

Greatly appreciated.

wb

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tabwb
post Mar 30 2023, 01:04 PM
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QUOTE(technicalninja @ Mar 29 2023, 10:33 PM) *

Before I dropped the engine, I would verify that the movement felt at the pully could also be felt in the flywheel access hole.

.250 is a bunch!


What was crank endplay during your build?




I honestly don't know - we didn't have the proper device to measure so we just used the same spacers that were present. I know, I know, we winged it and this is what we got...will be better next time.
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