Tip of the day - R&R the water pump and ... the fan belt stretcher

Evening everybody,

I have just spent the last few days installing my newly refurbished water pump (thank you Coventry West), new motor mounts, hoses and a new @#$%^&** fan belt. To be clear I have a 63 S1 3.8 with the double v pulleys, a fan belt tensioner/pulley and the original (I think) generator. The fan belt that I installed is part number C19524.

Everything went well until it came time to install the f! belt (and no, in the instance, the letter “f” is not an acronym for fan!!). I researched the archives and read about Mr. Mouton’s (RIP) bump the belt on method but could not get the f! belt to jump onto the pulley no matter how many times and approach angles I tried. So here are a few learnings and some photos for folks that are faced with what seems to be a fairly common issue:

1 - To remove and re-install the water pump, I was unable to remover the water pump c/w it’s pulley as it would foul frame components. I had to separate the water pump and it’s pulley in-situ, disconnect the motor mounts and jack up the engine a bit. This provided sufficient clearance so that the water pump and its pulley could be removed/installed as separate pieces.

2 - Despite MANY attempts to bump the fan belt onto the pulleys at various approach angles, it seemed the the belt was too tight. I am sure fan belts stretch after they are installed and tensioned so I decided to pre-stretch the new one. I slid the belt over the outside of my big bench vise jaw and the vise base (with a piece of rounded wood to smooth out the profile of the vise base) and then opened the vise a bit at a time to stretch the belt. I can tell you that them f! belts is real strong as I gave it the beans…slowly opening the vise a bit at a time over the course of 24 hours. A picture is attached to better illustrate the f! belt stretcher

3 - Even with the f! belt stretched, it still seemed too tight even when the generator was hard up against the engine. I realized that there is a casting lug on the front generator flange that fouls the water pump and one of the water pump mounting bolts. I took the generator out and used a dremel with a cutoff disc to remove the lug. I also removed the fouling water pump bolt. This allowed the generator to move in close to an additional 1/2 inch, which gave some more room to get the f! belt on. Before and after pictures of the generator are attached.

4 - When I researched Jerry M’s bump method of fan belt installation, I did not see any indication of which pulley to bump the belt onto. Initially I tried to bump it onto the generator pulley as the distance between the water pump pulley and the generator seemed to be the longest of all inter pulley distances. I found that this is not the best pulley to select. It turns out the best pulley to bump the belt onto is the water pump (note this is with the tensioner pulley fully retracted). The reason is that the water pump pulley has a tapered nose that allows the f! belt to be pressed inboard towards the sheaves. Once the f! belt was moved fully inboard on the tapered nose, I used a long prybar to lever the f! belt towards the sheaves while bumping the engine with a remote starter switch and then…Bobs yer Uncle, the f! belt jumped onto the pulley. A quick final tension on the generator and re-install of the removed water pump bolt and all was good.

Time to hit the Easy Button…not!

Cheers
Steve

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Thanks Steve,

Jerry had three extra fan belts in the boot for Mik and I recently replaced one on friends ‘64, two of the three were the smaller f’ belts and I couldn’t get them on her car so I tried the one that was used (much better condition than the cracked belt she had. I figure that when the belt breaks on Mik I’ll have to remove the alternator/dynator and fit it under the new belt then refasten the alt/generator. Not going to be a lot of fun so may have to come back and look at how you did it. Thanks for documenting your experience.
Cheers,
LLynn

There is something wrong - wrong belt or a wrong pulley somewhere. It is NOT that difficult to install the belt when all the right parts are used.

I’m with @Ray_Livingston on this, at least on a 4.2 S1, which may be completely different. I actually changed my fan belt by feel under a partial moon in the Nevada desert one night ca. 1972, with only the coyotes for company. Took an hour or so with the tools supplied by Jaguar in the tool roll, LOL!

I’m glad I had an extra belt, and have always traveleled with one, and also a set of water hoses.

Never give up Steve!

I like to use Gates belts from my a local store. They let me try as many as I like and return the ones that don’t fit.

Then there’s this:

Your welcome,
LLynn

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I think @chuck_goolsbee has a picture of him changing the belt on his Dad’s 120, by the side of the road…and it was NOT this glamorous!

:star_struck:

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Now that’s precious!

You know it’s fake, though, because she didn’t use any hand cleaner. :sweat_smile:

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I also have a 3.8 E-type with original Lucas generator and I have absolutely no trouble whatsoever fitting or removing the double-v belt…just loosen the generator, press the tensioner in and the belt goes fully slack.

This leads me to conclude that your belt is simply too short!

There shouldn’t be any need for power tools or finger-risking bump maneuvers. Get another belt.

Alan
N.J.

Grrr…my generator failed yesterday…not sure if it is the result of the fan belt being too tight or not. Now it is being rebuilt.

Nevertheless, it seems there are those that have no problem with their pulleys and fan belt with everything going on easily, and there are those who have experienced the same challenge I faced where the fan belt is very tight/too small and has to be bumped onto the pulley by using the starting motor.

I have looked for a slightly longer double v belt to resolve this issue but have not been able to locate one…and our local FLAPS are not keen on me poking around to find one.

So I thought it would be worth getting to the bottom of all of this and creating some institutional knowledge that might help future generations/challenges. I would appreciate it is some of those with the “right” equipment compare their car to the following dimensions measured off my car:

Pulley OD
Crank = 5 1/8"
Water Pump = 5 5/8"
Generator = 3 1/8"

Pulley Centre Line to Centre Line - Note the the figures below are a bit rough as it is a challenge to measure the dimensions precisely due to tight access and the offset of the tip of the crank/water pump/generator shafts
Crank to Water Pump = 7 1/2"
Water Pump to Generator= 6 7/8"
Generator to Crank = 9 3/4"

Note that I am using a C19524 double v belt with an OD of 39", which according the the usuals is the correct belt.

So…if any of you folks that have equipment that allows an easy to install fan belt would be willing to inspect and advise the dimensions of your vehicle, it would allow those of us challenged by this to resolve this problem.

Cheers
Steve…who’s belt is uncomfortable tight…and so is his fan belt!!

Had the same experience in my '68 ots , including the long legs in 1974. Alternator bearing crapped out somewhere outside Fargo N.D. No fixes there - needless to say. My companion removed one nylon stocking - I tied it around the crank pulley and water pump, bypassing the alternator, and made it back to Winnipeg about 4 hours later.

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Because I was a curious little person, I tried that trick on a Volkswagen: it made it about 5 miles. I tried it on my Datsun: it made it about 15 miles.

I found one of those pick-a-link belts, and put that in my cars as a spare.

Hmmmm, given the stocking trick, perhaps I’ll just repair the generator and reinstall everything as is…:japanese_ogre:

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You forgot to turn off the headlights, Paul. :grimacing:

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