Uprated water pump

[Guest kevinevenett]

I have had some trouble with my TR4 overheating.  Having checked the radiator and thermostat I thought maybe the water pump could be the problem, the top of the radiator is hot and the bottom stays cool.

 

I boiught an uprated water pump from David Manners but when I fit it into the housing it doesn't turn.  I have tried all three different orientations with the same result.  Has anybody experienced similar problems or do I just assume the part just isn't right?  It is supposed to fit all models from TR2 to TR4A.

[david ferry]

There have previously been a number of posts about this problem.

 

I think you may find that the pump may be 'at fault'.

 

Other earlier posts seem to suggest they are 'not very good quality'.

 

Read what you want into that!

 

Regards

[Guest kevinevenett]

Hi David

 

Thanks for the reply.  It seems that the uprated water pump is a no-no.  So is there anything else I can do with my overheating or to increase flow?  Head gasket seems ok so I'm running out of ideas.

 

Regards

 

Kevin

[marvmul]

Is the u/r pump spinning feely when it is not fitted to the engine? I bought an u/r pump a while ago : fastening the pulley nut caused the spindle to move forwards, and the rotor was touching the pump body. I send it back to the supplier but it never arrived, probably it arrived, but they could not locate it; in the end, I bought a second u/r pump and the same problem occured : after pressing back the spindel, and fitting the nut with less torque, I have had no problem anymore.

A friend of mine once fitted a standard new pump : the rotor was touching the pump housing and he had to remove some material of the rotor.

[Tr4Tony]

Hi kevin

 

I had a small batch of 4 cyl pumps made 'uprated' with big bearings etc. these work well. if youre willing to hang on im getting another bactch done.

 

Regards

 

Tony

[Mychael]

I've had two new pumps (not "uprated type") suffer early failures. They had bent shafts from new!!

I've done what Tony had suggested and used a local guy to improve an original pump, no problems since.

Are "uprated " pumps really necessary? I may be wrong but I was under the impression the the four bladed impellor pumps remained essentially the same right up till TR6. If they were ok for 150hp, then surely any overheating problems must be from another scource.

 

Mychael

[rudi]

Hi, all depends what you mean by overheating? And how about the reading of the gauge?  Other questions to ask: Did it "overheat" before or does it "overheat" all of a sudden? Has something been changed at the engine? What about the timing? How about the radiator, is it "clean"?I intend to say that a lot of so called overheating is not what it seems to be.

Good hunting, Rudi

[Don Elliott]

The water pump I bought from Cox & Buckles in 1987 had a cast iron impeller whereas the original pump had a bronze or brass one.  Both had four vanes.  I compared them closely and new new one in cast iron was smaller in diameter and in height.  I assumed it would pump less coolant, so I installed the original one onto a new stainless steel shaft I had made.  87,000 miles and 15 summers later, it is still working fine and has never leaked.  Most will leak where the mild steel shaft corrodes in the bore of the seal.

 

There is a debate among TR racers whether a higher capacity pump is the answer.  It sounds logical that it would cool better if there was a higher flow rate.  But many say the it does not stay long enough in the radiator to cool down.  It comes into the rad hot and flows through so fast that it leaves the rad while it is still hot.  What do others think ?

 

Don Elliott, TS 27489 LO, Montreal, Canada

TR Register member since 1987

 

http://www.britishcarforum.com/ubbthre....127

[Tr4Tony]

Cavitation - thats what i say - the six blade impellor pumps cause cavitation in the water (apparently) - I have to say that I run a standard pattern pump with a steel 4 blade impellor on my rally engine (and on others_ and have found no fault with the pumps.

 

Radiators and ducting are a different matter and shrouding the rad is critical to getting the air moving around it and also to feeding the carbs - in summer my weber'd 4 is a pig to run.

 

Forget the glitzy alloy six blade jobs i say - what do others think ?

 

Regards

 

Tony

[Mychael]

Original impellors better quality, smoother vanes and better shaped. The repro stuff is generally junk. Ok for cars that only get used occasianly but otherwise to be avoided at all cost.

 

Mychael

[MadMarx]

Have you thought about removing all the air in your engine?

 

Lift the car in the front, let the engine run with the heater on and fill up water. You can help by squeezing the lower hose to push all air out.

 

In most cases of overheating it is captured air.

 

Sometimes a leaking head gasket can result in overheating. Does your engine force out water under full throttle up hill?

 

So first I would try to fill up the system properly, then fitting a new head gasket if the problem is still present. If that all doesn't help maybe your radiator is blocked.

 

Chris

[unclepete]

One thing worth looking at is the Thermostat.

The original type have a shroud which allows water to bypass the radiator untill the temperature increases, then (and this is the important bit) when opening the water flow to the radiator the shroud closes off the bypass!

Standard Thermostats will fit and will allow flow through the radiator and the bypass which you don't want.

This will reduce your coolant flow though the Rad.

I have heard mention that some members who run their cars without Thermostats put a penny washer in the bypass pipe?

I'm not sure if this works

Unc

[Mychael]

I have placed a restrictor in the bypass pipe. does not seem to make a difference one way or the other.

 

Mychael

[Guest J Martin]

TR4 Tony

 

I have sent you an e-mail

 

Regards

 

John Martin

[unclepete]

I have placed a restrictor in the bypass pipe. does not seem to make a difference one way or the other.

Mychael

You don't mention if you have the correct Thermostat fitted or not.

If it is the correct one it won't make any difference whether you fit a restrictor or not.

 

Unc

[Mychael]

Have the correct "bellows/shroud" type. Correct, if all works as it should then theroetically should not be much if any difference.

More a "belts and braces" thing. It was suggested to me to put in the restrictor, the whole thing was apart already so it seemed like as good a time as any to install it.

Another thing I've seen done is to fit a pipe from the heater tap on the top of the block, then and assuming no heater fitted you run a pipe to connect it back into the water pump housing.

I don't have this fitted but have been told it helps alleviate any hot spots in the head, a mate of mine who races his car has it installed.

 

Mychael

[marvmul]

Another thing I've seen done is to fit a pipe from the heater tap on the top of the block, then and assuming no heater fitted you run a pipe to connect it back into the water pump housing.

I don't have this fitted but have been told it helps alleviate any hot spots in the head, a mate of mine who races his car has it installed.

More water goes to the front cylinders than to the rear cylinders : this must be a trick to get more water to the rear cylinders?

The same can be achieved by fitting a cylinderhead gasket with some of the holes for the water circulation omitted or made smaller : the gasket provides some resistance then, and each cylinder gets the same amount of the circulation and deposits of debris around the 4th cylinder is prevented. These gaskets can be bought in plain copper.

[Andrew Smith]

Hi Kevin

 

I've responded to this type of problem a few times now:

 

In 2003, my engine was rebuilt to 87mm with a lead-free head and suffered from intermittent overheating and air locks (top hose hot and bottom one cold).    

 

Given that the rad, pump(?), hoses and waterways are all ok, these are the measures that worked for me and are offered as general advice:

 

1.  Remove the rad cap and run the engine to temp, look for air bubbles and then after 5 -10 mins replace the cap - this should clear the sytem of air, but if this does not resolve the problem then:

 

2.  Dump the thermostat: I was running with the original bellows fitted and I've still got a number of these new and boxed if you want them!

 

3.  Cut out the centre mechanical parts from a modern wax type thermostat and fit it: this then acts as a semi-restrictor and backs up the water allowing it to cool in the rad. Without it, the water would just pass through the rad limiting cooling affect.

 

4.  Fit a restrictor in the bye-pass hose; otherwise the water will just circulate and "bye-pass" the rad for the most part. Without the restrictor there is a chance of creating local hotspots in the engine with consequent results!

 

5.  For the restrictor, I used a washer with a 1/4" hole (GHF314 from Moss is ideal) or you could use a 10p piece and drill it with either 1/8th or 1/4". You will need to use a second jubilee clip behind the washer to keep it in place and prevent it slipping down the hose under pressure. Ensure the washer/coin is fitted hard against the bye-pass housing outlet inside the hose.

 

6.  Use Shell Opitmax with Castrol Valve Master Plus, this reduces run-on in my case.

 

7.  Fit a Kenlow or similar. I fitted a 13" Kenlow Blower 2000 Series (13/B); this works a treat and fits neatly on the rad and is supported by the internal lip on the apron on a 3A.

 

8.  Definitely fit the rad ducting, this is often overlooked as discussed in other posts: it's a must.

 

9.  Finally, ensure the correct rad cap is fitted: 4psi (with rad neck extension (3A/4) and 7psi without: 4/4A) with the correct length neck otherwise water will just deposit itself under your car via the overflow tube. At one stage I was considering fitting the TR4 expansion bottle, but have now ruled this out entirely.

 

With all these measures in place my 3A now runs at 170-180f with outside temps up in the mid-eighties and only in heavy traffic does the Kenlow need to come on now. I've set this at 185f.

 

Hope some of this of use. Good luck

 

Cheers

Andrew

[Bully]

I had a similar problem about 10 years ago.

 

The rad was blowing steam, although the tempreture gauge and thermo switch for the kenlow were cold.

 

rad was not blocked, pump was OK.

 

I was tipped off to try the block drain tap, to see if anything comes out - nothing.

 

The problem is the water inlet and outlet are at the top of the block.   When you change the water, if you only drain the rad, there is still water left in the block.   If you don't flush the block, sediment collects, and blocks the waterways, particularly around the No4 cylinder.

 

If this happens, the water at No4 becomes super heated, and travels the shortest route out, back through the water pump to the top of the rad, and out of the cap.   The rest of the system remains cold.

 

I suggest you try the drain tap in the block - even remove it.   If no water flow, you probably have a similar problem.

 

You need to remove the head, and dig out the crud using a bent peice of wire.

 

I hope that helps.

 

e-mail me if you need more info.

 

Regards Bully

 

:cool:

[sforster]

I can confirm Don Elliott's remark about the upgraded pumps not allowing water to stay in the radiator long enough. I had a damaged water pump so I changed to a six blade pump and ran hotter in general and under stress much hotter, when I reverted back to a standard pump the car returned to running at 185.

Simon.

[jean]

I have the impression that there are more criterias involved here. IMHO, if the water is circulating too fast through the radiator it also means that it is circulating more often, so the effect on cooling could be the same.

Could it be that, to make maximum use of an increased number of blades, the pipes as well as the water channels have to widened. More blades in the same pump diameter mean less room for water, resulting in a blockage in the water flow what in fact works against an improved circulation, the faster they rotate the more blockage they are bound to produce.

So the only way to improve circulation might be to alter the shape of the blades, not the number, and probably modify the pipes.

jean

[Richardtr3a]

I fitted an up rated water pump from Darryl at Racetorations which has cups instead of blades. It works really well and was expensive.In the days when you could go to the local Triumph agent for parts, the pump came with the pulley already attached. After spoiling the previous pump I would now always fit a new pulley at the same time. I have also gone the expansion bottle route which works well for me. Good luck.

[Bryan]

As a last resort with overheating of my 4A back in the summer when we had some really hot weather down here in Cornwall I had the radiator flow checked(another story!) by a local "specialist" who said it was OK - but when his boss looked at it said the wrong core had been fitted.  It was recored with a higher efficiency core - more tubes per inch - I forget the proper term X or Z type -  and no more problems.  had to refit the thermostat to get it to warm up at all.  I also wonder about the accuracy of the gauge - anyone worked out a simple way of checking the gauge reading against the actual water temperature?

 

Bryan

[Don Elliott]

If you can unscrew the hex retaining nut securing the bulb into the housing, and if you can withdraw the bulb without destoying it (see this topic on another thread), you can immerse the bulb into a pan of boiling water to calibrate it at 100 deg. C (212 deg. F).

 

If you have a 50/50 mix of water and antifreeze, the mix will only boil at about 245 deg. F and with a 4 psi pressure radiator cap, this will  increase the BP to somewhere about 280 deg. F.  If the mix stays liquid, it will continue to transfer heat.  If it turns to steam, the heat transfer coefficient will change and the heat transferred will decrease, causing the engine to overheat.  To me, 250 deg. F is not overheating the liquid because it has not turned to steam.

 

But I have heard it said that each time you run the engine above the "normal" operating temperature, you can subtract 100 miles from the expected long term life of the engine.  I don't know where this originated and I don't know if it is true.

 

Don Elliott, Original Owner, 1958 TR3A, Montreal, Canada

http://mysite.wanadoo-members.co.uk/trebor/don3a_big.JPG