Author Topic: water pump rebuild update  (Read 2950 times)

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Offline YellowS4DHC

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water pump rebuild update
« on: Friday,August 16, 2013, 05:26:19 PM »
Last time I checked in, I was contemplating a water pump rebuild.  After seeing the play in the water pump pulley it was clear that now was the time.

As suggested by Brian, I removed the front cover with little difficulty with the engine in place.  I worked almost entirely from below and didn't camp out on the engine block as did Brian.  With the head already off, taking off the pan and the front cover were really fairly easy even though the work space is tight.  I don't think there will be any issues in getting a good seal on the front cover. The only downside I see is that some of the front cover bolts will have to be torqued by "feel" because torque wrench access is limited.

In taking the engine apart, I found that my block is not original, and in fact is a tall block 1600.  With .020 pistons and a 3" stroke, my displacement is around 1680 cc (wah-hoo!).  I'm told that the rough rule of thumb is about 10 hp for ever 100cc increase in displacement, so I'm not too upset about not having the original block.  The tall block does require a spacer on the top of the front cover which will need some special attention on reassembly as I suspect it was the source of one of my oil leaks.

Never know what you have till you tear it apart.   :)


regards
Rick

 

Offline EuropaTC

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Re: water pump rebuild update
« Reply #1 on: Friday,August 16, 2013, 11:00:58 PM »
In taking the engine apart, I found that my block is not original, and in fact is a tall block 1600.  With .020 pistons and a 3" stroke, my displacement is around 1680 cc (wah-hoo!).  I'm told that the rough rule of thumb is about 10 hp for ever 100cc increase in displacement, so I'm not too upset about not having the original block.  The tall block does require a spacer on the top of the front cover which will need some special attention on reassembly as I suspect it was the source of one of my oil leaks.

 :)  who's a lucky boy then ? 

I bet you were wondering what was with the extra spacer when you came to dismantle it, I know I'd have had several "duh" moments finding something like that. 

I checked the Dave Vizard "Tuning Twin Cam Fords" book because I remember he did a tall block TC but apart from a construction diagram for the spacer and machining to complete the job, there's not much else to add to what you'll already have found. He was taking the 1600 block up to 1800cc with 85mm pistons so if the head is still off it might be worth checking what size pistons you have there. You might have even more cubes than you think ! 

If it's of interest I can scan the pages and post them up. The one snippet I did find was a comment on compression ratio, which he reckoned came in at 12:1 with the 85mm pistons due to capacity increase, so it seems reasonable to assume you might be running a higher CR as well ?

Brian

Offline Bainford

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Re: water pump rebuild update
« Reply #2 on: Monday,August 19, 2013, 06:50:11 AM »
Sounds good Rick. I'm following this project with interest as I have wondered if could be done. Also interesting regarding the 1600 tall block as I've considered screwing one of these together myself some day. Cheers.
The Twin Cam plays the symphony whilst my right foot conducts the orchestra. At 3800 rpm the Mad Pipe Organ joins in.

Trevor

Offline YellowS4DHC

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Re: water pump rebuild update
« Reply #3 on: Monday,August 19, 2013, 07:21:00 PM »
I'm very glad I gave it a go as it really doesn't appear to be that hard to do a water pump job with the engine in situ.  As I mentioned at the outset, I already had the head off so I had nothing to lose by trying.  We'll see how the reassembly goes.  Thank you Brian for the encouraging words. ;)

BTW, have you folks that have rebuilt water pumps noticed a fair bit of stiffness after the impeller is pressed on?  My pump's shaft turned nicely with little drag after being pressed in place, but after I pressed on the impeller (thereby putting pressure on the spring seal) it got pretty stiff.  It was well lubricated prior to final assembly.  Just wondering, it turns smoothly, it's just stiffer than I would like.  My rebuild kit came from Dave Bean and looks to be of reasonable aftermarket quality.

All in all, I'm quite pleased with this "pig in a poke" TC I bought off ebay last sept.  Some distant PO really tinkered with this thing 10-12 yrs ago and the stroker engine is just one of several neat things I am happy to have got.  At this point, I'm tempted to install a high lift intake cam and have some work done on the intake and exhaust ports.  Still thinking that over, but now would be a good time to do it.  I'm a little concerned about the robustness of the gearbox, as I suspect I might be approaching 130-135 hp.

Regards
Rick

Offline EuropaTC

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Re: water pump rebuild update
« Reply #4 on: Monday,August 19, 2013, 10:32:05 PM »
I honestly can't recall if the assembly was stiff or not Rick, the last one I did was my Elan which was 2yrs ago now and for me that's almost a lifetime.....   

I can only remember setting up the clearances with a couple of sets of feeler gauges and pressing it into place with the bench vice. As a pure guess I think I'd expect a new seal to have reasonable friction until it had been lubricated and turned a few times to bed in ?

If you're thinking of further engine tuning, then maybe work on the head porting should be first on the list ? Even if you retain the cams, cleaning up progress for petrol & exhaust gases never does any harm and now must be the best time to do it.

The other thing to consider is the valves sizes that the PO used ?  Again whilst the head is off is the best the time to fit larger valves, you can go up to 1.6" IIRC and these will still work happily with standard cams if you want to take the tuning in stages.  The cams can always be changed later when everything is running, and even moving from standard TC to the TCS cams will mean re-jetting the carburettors so the bill starts to mount up at that point.

Brian

Offline YellowS4DHC

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Re: water pump rebuild update
« Reply #5 on: Tuesday,August 20, 2013, 09:33:34 PM »
Brian,
A little background: my stroker "big valve" currently has SE cams with dual HS6 SU carbs and a 43D distributor (max advance is 33-34 deg).  Bore is .020 oversized (3.270"), hence my displacement is just under 1700 cc's.  CR is believed to be somewhere around 9-9.5 as I am able to use 91 octane with no pinging.  It's expensive to get high octane gas, so I'd like to keep the TC's CR close to where it is now. 

Porting would be at the top of the list, I definitely agree.  I will likely do that in any case.  However, as the head is already off, now would be a good time to also prep for a higher lift cam.  I will need stiffer valve springs.  Also, I'll need to make sure there is no coil bind nor interference with the pistons for the specific cam intended to be used.  So, I'll probably have the porting work done at the same time I have the springs replaced and coil bind checked.  Based on my piston configuration and deck height, I believe I have adequate dynamic piston/valve  clearance for a .380-.390 lift cam.  I may have to get different needles for the SUs, but that's not too big a deal. The primary obstacle at this point is $$$$$$ for the cams and machine work.

regards
Rick

Offline EuropaTC

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Re: water pump rebuild update
« Reply #6 on: Wednesday,August 21, 2013, 01:43:43 AM »
Hey, this is sounding interesting, a real find.

I agree on trying to keep CR within limits, over here I use regular unleaded but put an octane booster in the Elan which has a slightly higher CR than the Europa, it's a pain.  We can get 98-99 octane but living where we do there's no garages selling it.

It does make sense to check the valve springs/seats if there's a chance of fitting different cams, and of course whatever new cam you get it's going to cost big bucks for a Europa inlet cam. After that a pair of new needles in the SUs is going to be peanuts !

Let's know how you get on with it, it's a good project to have.

Brian