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Leaky water pump options

PostPosted: Mon Jun 10, 2019 6:38 pm
by holywood3645
Got the drip! Repair options....
It?s the OEM style pump, and engine will be pulled. I?m considering the
1) electric water pump.
2) Cassette style pump.
3) replace OEM style
The car is used in a hot climate (S.Cal) and often stuck in traffic. And low water circulation a low RPM appears to be a common reason for temperature spikes. This would suggest the electric pump option may be a favorite.
I?m interested in comments on option 1 & 2...
if I go electric what mods (OEM impeller removal possibly) or what mods are needed.

I?m also considering some engine refresh, and possibly fitting oil seals on the valves. This would (I believe need new guides) Have there been any successful installs of the seals and any recommendations who in the US can do the work.

Funny, this happens now when the engine is performing so well...

Thanks
James

Re: Leaky water pump options

PostPosted: Mon Jun 10, 2019 8:00 pm
by el-saturn
howdy - as your in s.cal, you MUST contact americas best (vely blitish), his name is tony ingram from st barbara - i think his site is lotus 7.com ------- youll find him. many moons ago i purchased a lotus 23 frank which we sent to europe for 80 dollahs (forged by farndon back in 1965) Sandy (from OR and Mill Valley, origanaly)

Re: Leaky water pump options

PostPosted: Tue Jun 11, 2019 4:34 am
by StressCraxx
Hello James,

I have the Bean cassette kit in my Elan. It works really well, doesn't leak oil or coolant. The impeller is the same diameter as original, so I keep the idle at 900-1000. I've had it for more than 12 years and no issues at all.

The real heat issue is expelling the heat from the rad with the fan. I have had to turn the interior heat up to max on 100F days here in the Bay Area. No fun. The best way is to install a pusher electric fan. The SPAL 30102030 or 3012045 with a thermostat on a relay work really well.

How is the Timex Escort coming along?

Best regards,
Dan

Re: Leaky water pump options

PostPosted: Tue Jun 11, 2019 5:20 pm
by tvacc
I have to agree with the above post. Have the same on both my Elans. No issues and looks almost original.

Edit, I never have to open the interior heat louvers. Nor turn on the fan. Cars stay cool. On one of my Elans the fan works all the time. No thermostat on the fan.

Re: Leaky water pump options

PostPosted: Tue Jun 11, 2019 5:29 pm
by Mr.Gale
This is what I did and it is working great. https://youtu.be/I9No_RTRGIE

Mr.G

Re: Leaky water pump options

PostPosted: Tue Jun 11, 2019 7:11 pm
by RichardHawkins
James,

I can't comment on water pump. I chose electric, but the vehicle is still in bits.

For valve stem seals, there is a man in Sanfrancisco called Keith Franck who runs a web site called vintagetechnologygarage, if I remember correctly he has fitted valve stem seals.

Hope this helps,

Richard Hawkins

Re: Leaky water pump options

PostPosted: Tue Jun 11, 2019 7:46 pm
by JonB
I read a post about valve stem seals. It said not to fit them as they will prevent oil getting into the guides to lubricate them. The TC engine uses oil by design.

Err... discuss.. :)

Re: Leaky water pump options

PostPosted: Wed Jun 12, 2019 1:17 am
by 2cams70
JonB wrote:I read a post about valve stem seals. It said not to fit them as they will prevent oil getting into the guides to lubricate them. The TC engine uses oil by design.

Err... discuss.. :)


Even a standard Ford crossflow pushrod engine does not have full valve guide seals. It has what are termed "umbrella seals". The rubber seal is umbrella shaped, locates positively on the valve stem and rides up and down with the valve. The umbrella shape serves to deflect excess oil from reaching the guide. It is not a positive seal as such. Millions of crossflow engines produced. Never been a significant concern.

One a Twin Cam you already have a big umbrella sitting over the valve stem - it's called a cam follower. Why do you still need a positive seal on the Twin Cam in that case?

Re: Leaky water pump options

PostPosted: Wed Jun 12, 2019 12:10 pm
by types26/36
JonB wrote:I read a post about valve stem seals. It said not to fit them as they will prevent oil getting into the guides to lubricate them. The TC engine uses oil by design.Err... discuss.. :)


Modern valve seals are designed to let a small amount of oil past to lubricate the stems.
I fitted valve seals after haveing the guides replaced thee times and it still smoked, perhaps I was just unlucky but now it no longer smokes even on start up.
I don?t do a lot of mileage so doubt a wear issue will be a problem, I did not even bother to check the valves when I recently removed the head to replace the water pump as it was running fine.
As mentioned previously Keith Franck of Side draft Central (who used to be a forum member) also fitted seals and Keith is a very clever person, if its good enough for him then its good enough for me.
Here is an interesting article about valve seals for anyone interested and a snip from it if you dont want to read the whole thing.
https://www.enginebuildermag.com/1998/0 ... d-designs/

Re: Leaky water pump options

PostPosted: Thu Jun 13, 2019 4:27 am
by 2cams70
The valve guide seals no doubt help once the guides become worn or if the guide has been machined incorrectly with excessive stem to guide clearance. If the guides are worn (and they'll become worn more quickly if there's not enough oil supply) it's arguable that the head should be pulled down for repair anyway.When that article talks about OHC engines needing seals especially they are probably talking about things like 2.0 Ford Pinto OHC engines that still have rocker arms and not follower buckets that cover the valve stem.

Re: Leaky water pump options

PostPosted: Thu Jun 13, 2019 9:22 am
by JonB
Well that is very interesting indeed. Thanks! :D

Re: Leaky water pump options

PostPosted: Thu Jun 13, 2019 9:39 am
by types26/36
2cams70 wrote:.When that article talks about OHC engines needing seals especially they are probably talking about things like 2.0 Ford Pinto OHC engines that still have rocker arms and not follower buckets that cover the valve stem.

I don't think so, all modern OHC engines use valve seals and I cannot think of one that does not, this includes those that have buckets (cam followers) above the valve example: the VW Audi range.
I believe the only reason Lotus did not fit them was because due to the design of the engine there was simply not enough space and back in 1962 the seal technology had not been developed sufficiently , OHC engines were a still quite exotic as most run of the mill cars were running about with SV or OHV engines.
I heard to get over the issue Lotus supplied their dealers with a special reamer to ream to fine tolerances but this was just a compromise.
Lotus recognized the issue and modified the later cyl.heads adding an extra oil drain back channel to get the oil away from number 4 valves, this can be seen on the later heads and has a banking plug adjacent to no.4 exhaust port.
I am not advocating everybody should fit seals as it involves machining and careful measuring to prevent crushing the seal plus it cannot be done with cams that have a lift higher then the Sprint cam.
I myself run one engine with no seals and another with seals, the unsealed engine has a slight wiff of smoke but is not excessive and the sealed non.
In conclusion if an engine is not smoking ...good but I am just replying to the OP and JonB as they asked about seals and the pros and cons.

Re: Leaky water pump options

PostPosted: Thu Jun 13, 2019 10:39 am
by 2cams70
types26/36 wrote:I don't think so, all modern OHC engines use valve seals and I cannot think of one that does not, this includes those that have buckets (cam followers) above the valve example: the VW Audi range.


I'm aware all modern engines have valve stem seals. The design requirements for modern engines are worlds away from what they were back in the LTC days. Number 1 criteria is emissions, number 2 is fuel economy, number 3 is durability and number 4 is performance. In another 15 years or so the internal combustion engine will likely be banned! It goes without saying that valve stem seals are essential to meet emission targets.

On a LTC however I would argue that the benefits aren't that great - eliminating the odd puff of smoke and reduced oil consumption versus the disadvantages - inability to run high lift cams, cost and possible reduced guide life.

I say enjoy the dirty, smoky, noisy, politically incorrect internal combustion engine in it's full glory whilst we still can!

Re: Leaky water pump options

PostPosted: Thu Jun 13, 2019 11:18 am
by rgh0
As 2Cams70 says the benefits of valve stem seals on a twincam are limited and if its built right they are not really needed and will probably accelerate valve guide wear to some degree.... which you can live with as the seal will help stop the resultant leakage but it does not stop the poor valve seat sealing due to the valve moving on the seat due to guide wear.

The buckets do not really do anything to stop oil leakage down the guides if the clearance is excessive as there is plenty of oil mist in the head everywhere under the cam cover and the inlet ports are under negative pressure so that oil is sucked down the guides.

On the exhaust side leakage is less of an issue when running as there is no negative pressure sucking like on the inlet side at idle with the throttles closed. Lotus added the drain from the rear of the exhaust side to the inlet side as drainage to the front of the head from cylinder 3 and 4 is obstructed by the water thermostat outlet thus the oil level in cylinders 3 and 4 on the exhaust side is normally above the top of the valve guides without this drain and when the car is stopped it drains down the guides into the exhaust and burns on startup.

chewers
Rohan

Re: Leaky water pump options

PostPosted: Thu Jun 13, 2019 8:20 pm
by bulfin
I have an electric water pump and works great. I am in Alabama so the heat and humidity are high.

(After saying this, it will probably break tomorrow)

Bob