Fan positioning

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jake@facewest.co.uk
Posts: 59
Joined: 23rd May 2018 - 10:54pm

Fan positioning

Post by jake@facewest.co.uk » 14th October 2018 - 1:49pm

Bit of a weird one.

Did the valves today. 1600 Type 3 Fastback. Rotated Rotor (on generator pulley) to be in number 1 TDC mark.

Looked at the fan marking through the inspection hole expecting to see some marks, none at all. On rotating the engine there are a lot of marks, the original factory one but others marked with paint. None of these really gave any useful info.

I checked the valves anyway going off the rotor position and all seemed spot on. Engine runs really nicely.

However that made me think that maybe the fan isn't on properly. Since I won't have timing marks for the ignition timing.

Is it possible to put the fan pulley on incorrectly? Say 90 degrees out? I don't think you can on a T1, but not taken it off before on a T3.

Cheers, Jake.

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broady_6
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Joined: 13th January 2009 - 8:55pm

Re: Fan positioning

Post by broady_6 » 14th October 2018 - 3:09pm

It shouldnt be possible as there is a locating peg in the "impeller" which lines up with a hole in the fan. If that has been removed/lost at some point then it can go on in any orientation.

The bit you were looking at yesterday is what i refer to as the impeller (just to aid clarity so people know which of the two fans im talking about)

There isnt just one factory mark, depending on your engine it will have a number of marks indicating 0 5 7.5 and 10 degrees. If you post a photo im sure we can figure it out
The sultan of swing

jake@facewest.co.uk
Posts: 59
Joined: 23rd May 2018 - 10:54pm

Re: Fan positioning

Post by jake@facewest.co.uk » 14th October 2018 - 5:51pm

It's a bit odd. There are no marks anywhere near the inspection hole when No1 is at TDC. Verified by notch in Distributor lining up with rotor. And that's where No1 HT lead is too. Plus valve gaps all correlate when I turn the engine and measure.

There are marks on the Fan:
Image

But these marks line up when the rotor is miles away from No1. More than 70degrees away. So it can't run if the timing was that far out (Runs really nice!)

I'll get a timing light and see if that shows up anything when it's running.

Probably doing something really stupid, just need to figure it out.

Thanks.

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broady_6
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Joined: 13th January 2009 - 8:55pm

Re: Fan positioning

Post by broady_6 » 14th October 2018 - 6:57pm

Here is the various timing marks, check your engine code as you may have carbs now but it could have been FI when new.

http://www.hallvw.clara.net/type3ign.htm

If the key from the crank or dowel in the impeller is missing then its possible for it not to line up and the interference fit would be enough to keep it driven. Its not a huge job to take it off an check. But as its running ok Id wait for the winter months and spare a sunday afternoon.
The sultan of swing

jake@facewest.co.uk
Posts: 59
Joined: 23rd May 2018 - 10:54pm

Re: Fan positioning

Post by jake@facewest.co.uk » 15th October 2018 - 8:42pm

Thanks Broady. I'll take it off and check.

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