TR4 Water Pump & Belt

[Andy Field]

Apologies if this topic has been covered before.  I have some issues concerning the water pump and belt on my 1962 TR4.  To remove the belt, I have to knock of the water pump pulley as well as I cannot gain enough slack in the belt (20 x 900mm) to pull over any of the pulleys even with the dynamo in its closest position to the engine.  If this is the norm is a longer belt available?  I have also noticed that when I have fully tightened the pulley nut, the pulley is about 5mm inboard of the other two pulleys so the belt is angled inwards towards the engine on its route from the dynamo pulley to the water pump pulley.  Should the pulley automatically locate in the correct position on the pump shaft?  Also I have now replaced the bolt to the pump housing with a stud, however the inner face of the pulley will contact the end of the stud when the pulley nut is tightened fully.  As far as I can make out, the pump, pulley, the dynamo mounting brackets etc all seem to be the correct items.  Hope this makes sense!  Ideas and solutions most welcome.

Many thanks

Andy

[RogerH]

Hi Ady

do you have the original thick bely or the modified thin belt??

The thin belt is easier to play with and there are many/various sizes.  The thick belt less so

To get either belt on or off you sometimes need to use a lever to prise it over the pulley edge whilst rotating the pulley.

Before you swapped the bolt for a stud did everything fit. If so can't you simply reduce the stud length.

Is the pulley new??

What type of fitment does it have  - taper shaft or straight shaft with a shoulder>  If straight then can you space it out with a washer etc.

 

Roger

[RobH]

I don't think you will find any direct alternatives to the 900mm x 20mm solid wide belt Andy.  I use a 17mm BX section cogged belt - it sits a little deeper in the pulleys but is much more flexible than the standard one and they are available in a variety of lengths. e.g.:

https://simplybearings.co.uk/shop/Belts-V-Belts-BX-Section-Cogged-V-Belts-17x11mm/c4601_4790_4699/index.html?selection=BX+Section+Cogged+V+Belt

 

[Andy Field]

33 minutes ago, RogerH said:

Hi Ady

do you have the original thick bely or the modified thin belt??

The thin belt is easier to play with and there are many/various sizes.  The thick belt less so

To get either belt on or off you sometimes need to use a lever to prise it over the pulley edge whilst rotating the pulley.

Before you swapped the bolt for a stud did everything fit. If so can't you simply reduce the stud length.

Is the pulley new??

What type of fitment does it have  - taper shaft or straight shaft with a shoulder>  If straight then can you space it out with a washer etc.

 

Roger

Hi Roger, the belt is the original 20mm wide version. The pump has a straight shaft with no shoulder so the inside part of the pump, where the keyway slot is, does appear to rub on the pump where the shaft exits the pump body when the nut is fully tightened. There seems to be a initial rubbing noise on starting the engine that I think comes from the metal to metal contact at that point.  I have temporary fitted three fibre washers as a spacer to align the belt. This also clears the pulley from the stud.  The spacer will need to be more substantial than the fibre washers I guess but I am wary of the metal to metal contact if I fit a steel spacer. I would have thought the pump shaft would have been tapered or shouldered.  I had only noticed the belt misalignment when I was doing a winter strip down of the timing cover and crankshaft pulley etc for which I have another question about engine height in relation to the cross tube but that is for another day!

Thanks

Andy

[Andy Field]

54 minutes ago, RobH said:

I don't think you will find any direct alternatives to the 900mm x 20mm solid wide belt Andy.  I use a 17mm BX section cogged belt - it sits a little deeper in the pulleys but is much more flexible than the standard one and they are available in a variety of lengths. e.g.:

https://simplybearings.co.uk/shop/Belts-V-Belts-BX-Section-Cogged-V-Belts-17x11mm/c4601_4790_4699/index.html?selection=BX+Section+Cogged+V+Belt

 

Thanks for that Rob. Do you know length of belt you have fitted?

[BlueTR3A-5EKT]

30 minutes ago, Andy Field said:

Hi Roger, the belt is the original 20mm wide version. The pump has a straight shaft with no shoulder so the inside part of the pump, where the keyway slot is, does appear to rub on the pump where the shaft exits the pump body when the nut is fully tightened. There seems to be a initial rubbing noise on starting the engine that I think comes from the metal to metal contact at that point.  I have temporary fitted three fibre washers as a spacer to align the belt. This also clears the pulley from the stud.  The spacer will need to be more substantial than the fibre washers I guess but I am wary of the metal to metal contact if I fit a steel spacer. I would have thought the pump shaft would have been tapered or shouldered.  I had only noticed the belt misalignment when I was doing a winter strip down of the timing cover and crankshaft pulley etc for which I have another question about engine height in relation to the cross tube but that is for another day!

Thanks

Andy

Pulley position

Has the inside face of the pump that  abuts the pump front bearing worn?   Not uncommon if the pulley has run loose at some point and chattered on the shaft.   Have a look inside the pulley to see what state the woodruff key slot is like.   if worn replacement pulley may fix your issue.   The pulley should not touch the end of the correct stud (3” long) that holds the pump to the pump housing on the engine.

 

Edited February 7, 2022 by BlueTR3A-5EKT

[RobH]

34 minutes ago, Andy Field said:

Do you know length of belt you have fitted?

Yes mine is 965mm but I have an alternator with a custom- made smaller diameter pulley, so you may need something different. 

Edited February 7, 2022 by RobH

[Z320]

Hi Andy,

a 20X900 is not automaticly 900 mm long.

Ciao, Marco

Edited February 8, 2022 by Z320

[Z320]

yours could be a minimum wider, running higher on the pulleys,

this makes the belt like being "shorter"

Edited February 8, 2022 by Z320

[Andy Moltu]

Time for a thin belt conversion?

1) Available in a near infinite range of lengths.

2) Can be changed much more easily.

3) Arguably more reliable as the wide belts may not suite the higher revs used in the TR application v tractor revs. (May be compounded by spec of replacement wide belts compared to OEM and new old stock likely to have deteriorated.)

4) If your pulley stud is fouling the pulley it suggests something is wrong. Wrong stud?

[Bfg]

14 hours ago, Andy Field said:

 I have also noticed that when I have fully tightened the pulley nut, the pulley is about 5mm inboard of the other two pulleys so the belt is angled inwards towards the engine on its route from the dynamo pulley to the water pump pulley.

My first impression on reading this is that the wrong pulley (&/or pump) is fitted to your car.  That of course can happen over 60 years of various owners.  I've recently swapped mine because the pulley worked loose. Upon investigation I found there to be no woodruff key fitted. Fortunately my friend Rich happened to have just bought some to be refurbished and so we swapped the pulley, but the woodruff key was a different size.  It got me home and then I swapped the pump to that from which the pulley came off.  Here's a photo of that now fitted. . .

 

^ As you can see the pulley could not move back 5mm because it would foul the mounting studs. The belt I use is a 20 x 900 which I replaced for new last year.

I'm very fussy not to buy old-stock rubber parts and I'm sure this one is either from Continental or Gates.  I presume by the fact that I had a choice of new rubber, means that this size is still used in other applications such as mobile generators or water pumps, &/or with factory machines.   You can see how it fits into the Vee of the pulley. 

^ this shows the dynamo adjuster on my car, happens to be rather too long.  There's about 1/2" inward adjustment that allows the belt to come off and be refitted without prising ..albeit perhaps not very easily for those with slender hands.   But you can also see the fit of the belt into the vee of that pulley. 

One of the very great benefits of these wide belts is how slack they can be fitted ..without incurring slip. This in turn directly relates to less sideways loading on the bearings of either the dynamo and water pump. The belt's block-size means it doesn't flay around.  I might only presume these belts proved to be adequately reliable and long lived in early TR competition. 

Hope the photos help.

Pete

[stuart]

4 minutes ago, Bfg said:

.  I might only presume these belts proved to be adequately reliable and long lived in early TR competition. 

 

Pete

It is possible and I know from experience that after a long period of very high speed when suddenly slowing down the belt will flip off. It also a known problem in competition with the six cylinder cars too and they run the thin belt as standard.

Stuart.

Stuart.

[Bfg]

Thanks Stuart, I've not come across that with a wide belt before, but might easily imagine it could happen where the belt is fitted and forgotten.  Its obvious visual slackness is not a prompt to check its tension. 

Mind you I guess my days of very-high-speed driving in an old car (..put together by experts !) are mostly over, as with experience comes wisdom   if only in cautionary terms ..that muggins here will have to fix and  pay the bill when things let go. 

Cheers, Pete

[stuart]

Just now, Bfg said:

Thanks Stuart, I've not come across that with a wide belt before, but might easily imagine it could happen where the belt is fitted and forgotten.  Its obvious visual slackness is not a prompt to check its tension. 

Mind you I guess my days of very-high-speed driving in an old car (..put together by experts !) are mostly over, as with experience comes wisdom   if only in cautionary terms ..that muggins here will have to fix and  pay the bill when things let go. 

Cheers, Pete

The belt in question was at the nominal tightness for that sort of fitment but it was run at 5000+ RPM in top overdrive for at least an hour on a very cold night on a long run home.

Stuart.

[Z320]

16 hours ago, RobH said:

Yes mine is 965mm but I have an alternator with a custom- made smaller diameter pulley, so you may need something different. 

Smaller pulley and narrower Bx17 belt?

You use a BX17 x 865 mm belt, not 965 mm?

Edited February 8, 2022 by Z320

[RobH]

Smaller in diameter not width  - I want the alternator to rotate faster than it would with a dynamo pulley. (The belt width makes no difference to speed as it sits lower in all  the pulleys so the ratios remain the same.) The belt is marked 965  which is the exterior length.  The alternator bracket is my own so the length will probably be a bit different from others.  This view is a bit distorted - the pulleys are actually in line as they should be. 

Edited February 8, 2022 by RobH

[Andy Field]

19 hours ago, RobH said:

Yes mine is 965mm but I have an alternator with a custom- made smaller diameter pulley, so you may need something different. 

Understood - thanks for the reply Rob

[Andy Field]

19 hours ago, BlueTR3A-5EKT said:

Pulley position

Has the inside face of the pump that  abuts the pump front bearing worn?   Not uncommon if the pulley has run loose at some point and chattered on the shaft.   Have a look inside the pulley to see what state the woodruff key slot is like.   if worn replacement pulley may fix your issue.   The pulley should not touch the end of the correct stud (3” long) that holds the pump to the pump housing on the engine.

 

Hi Peter,

I purchased the stud, to replace the bolt,  from Moss so I presume it is the correct length and I did screw it into the block as far as it would go. The inside pulley will not not rub on the end of the stud when I position the pulley on the pump shaft in alignment with the other two pulleys. Only when I fully tighten the nut does the pulley move out of alignment (i.e. in towards the engine) and makes contact with the end of the stud.  There was not an issue when the bolt was installed but I had not noticed the pulley mis-alignment then, however the inside of the pulley was making contact at the point where the shaft exits the pump (I dapped some white marker on the end of key slot). The woodruff key and slot are not worn and the pulley is tight on the shaft.  Would the tension in the belt naturally align the pump pulley with the other two - otherwise how is the pulley aligned if there is no taper or shoulder on the pulley shaft?  The pump and pulley appear to the correct items - it even has a grease nipple.  I have purchased another pump and pulley but looking at it I am going to have the same issue (also came with no woodruff key)- so that's going back!

[Z320]

Rob, that's interesting...

Edited February 8, 2022 by Z320

[Andy Field]

6 hours ago, Bfg said:

My first impression on reading this is that the wrong pulley (&/or pump) is fitted to your car.  That of course can happen over 60 years of various owners.  I've recently swapped mine because the pulley worked loose. Upon investigation I found there to be no woodruff key fitted. Fortunately my friend Rich happened to have just bought some to be refurbished and so we swapped the pulley, but the woodruff key was a different size.  It got me home and then I swapped the pump to that from which the pulley came off.  Here's a photo of that now fitted. . .

 

^ As you can see the pulley could not move back 5mm because it would foul the mounting studs. The belt I use is a 20 x 900 which I replaced for new last year.

I'm very fussy not to buy old-stock rubber parts and I'm sure this one is either from Continental or Gates.  I presume by the fact that I had a choice of new rubber, means that this size is still used in other applications such as mobile generators or water pumps, &/or with factory machines.   You can see how it fits into the Vee of the pulley. 

^ this shows the dynamo adjuster on my car, happens to be rather too long.  There's about 1/2" inward adjustment that allows the belt to come off and be refitted without prising ..albeit perhaps not very easily for those with slender hands.   But you can also see the fit of the belt into the vee of that pulley. 

One of the very great benefits of these wide belts is how slack they can be fitted ..without incurring slip. This in turn directly relates to less sideways loading on the bearings of either the dynamo and water pump. The belt's block-size means it doesn't flay around.  I might only presume these belts proved to be adequately reliable and long lived in early TR competition. 

Hope the photos help.

Pete

Hi Pete,

Thanks for the images. They will probably assist me in comparing pulley position with my own. I take it that your water pump pulley aligns with the other two? My belt will not come off without knocking off the water pump pulley and that cannot be right. Not sure whether the belt would even prise on/off even with the dynamo full slacked off.  If you have a moment could you kindly measure the diameter of the dynamo and water pump pulleys so i can compare with my own - many thanks.

Cheers

Andy

[Bfg]

I'll check them for you tomorrow Andy, but as it happens I have the old / replaced water pump in my left hand (..as one does ! ) ..and its pulley's outside diameter is 4-3/16" (107mm).  Inside diameter is approximately 2-7/8" (73mm).  The offset from the pump's gasket face to belt axis / centre of vee is 1-7/16" (37mm) this is however an estimate as this pulley was previously spinning on its spindle (..no woodruff key) and its worn so badly that it no longer sits true on the spindle.  NB. the top inside width of this pulley's vee is 5/8" (16mm) and although a "Flennor" 20x900 LI belt was fitted - it rode high in this pulley, projecting a couple of mm above its rim. Conversely, the inside's bottom two thirds of the pulley's vee was not used (the paint is still in there).

And having put the water pump down.., I now have the car's old dynamo resting on my left knee (it's too heavy to have in my hand for very long !).  ..and its pulley's outside diameter is 3-7/32" (82mm). Its inside diameter is approximately 1-7/8" (47.5mm).  From the front face of the dynamo (excluding the raised bosses) there's an offset to the belt axis / centre of vee of approximately 1-1/8" (29mm).   NB. the top inside width of this pulley is a tad less than 3/4" (19mm), so although I don't have photo of its installation - the belt fitted all the way into the vee (as my previous photo indicates, which shows its replacement). And this fit is reflected by the polished inside face of the pulley's vee (..the paint is still in its bottom corner by 1/16").   

Hope that helps.

Pete.

[Andy Field]

1 hour ago, Bfg said:

I'll check them for you tomorrow Andy, but as it happens I have the old / replaced water pump in my left hand (..as one does ! ) ..and its pulley's outside diameter is 4-3/16" (107mm).  Inside diameter is approximately 2-7/8" (73mm).  The offset from the pump's gasket face to belt axis / centre of vee is 1-7/16" (37mm) this is however an estimate as this pulley was previously spinning on its spindle (..no woodruff key) and its worn so badly that it no longer sits true on the spindle.  NB. the top inside width of this pulley's vee is 5/8" (16mm) and although a "Flennor" 20x900 LI belt was fitted - it rode high in this pulley, projecting a couple of mm above its rim. Conversely, the inside's bottom two thirds of the pulley's vee was not used (the paint is still in there).

And having put the water pump down.., I now have the car's old dynamo resting on my left knee (it's too heavy to have in my hand for very long !).  ..and its pulley's outside diameter is 3-7/32" (82mm). Its inside diameter is approximately 1-7/8" (47.5mm).  From the front face of the dynamo (excluding the raised bosses) there's an offset to the belt axis / centre of vee of approximately 1-1/8" (29mm).   NB. the top inside width of this pulley is a tad less than 3/4" (19mm), so although I don't have photo of its installation - the belt fitted all the way into the vee (as my previous photo indicates, which shows its replacement). And this fit is reflected by the polished inside face of the pulley's vee (..the paint is still in its bottom corner by 1/16").   

Hope that helps.

Pete.

Thanks for the info Pete - very much appreciated.