I thought I'd chime in here with my experience in the last couple of months. Prior to the thread starting, I had the same leak on my 427 Windsor. Initially, I thought it was a crack in the front engine cover, but indeed... it was a threaded hole where coolant was leaking. In addition, I had coolant dripping on the damper _and_ from another hole further down on the cover.
What was most surprising is that they all seemed to appear at the same time? Coincidence, I guess....
The latter leak was due to the engine builder forgetting to put a bolt in the hole. I hadn't noticed this until it started leaking. This meant I had to pull the damper off to get a bolt into the hole. Ever tried to pull a damper on a GT40 with the engine in the car? Not trivial.
I now have a 'specially modified for GT40' damper puller... :laugh:
As for the engine builder... let's not go there. :furious:
I removed the water pump to find the other leaks and it was just as described in this thread. Too bad the thread started after I had the experience.
:sad:
Anyway, the leak dripping on the damper was coolant coming from the weep hole described by others. Coolant was leaking by the gasket around the unused bolt hole and coming out the threaded hole (which is not used by the water pump I have) and also into the cavity between the front cover and the water pump back plate. As also described in the thread, the back plate of my water pump looked like it came out of a 20 year old car... very corroded. The impeller also looked pretty sorry. Probably from the same reasons mentioned... straight water being used on the dyno and then the engine sat for awhile.
I have/had a Ford Motorsports M8501 E351S water pump on the car. The water pump was new when I received the car/engine and is the 'shorty' model people have been talking about. You can go to an Autozone and find a similar water pump that would fit, has the same casting marks and is made by the same company, but it's too long. I could not find the 'short' one. So I ordered a new FMS one from JEGS.
I should also note that I could NOT find a ready made gasket for the pump to back plate. Everyone expects you to buy a new or rebuilt water pump which includes this gasket installed under the back plate included. The only gasket I could find was the one between the plate and the front cover.
In the meantime, I was informed that the FMS water pumps were 'crap' and started asking around. Sure enough, multiple people on the Pantera list and elsewhere gave me firsthand experiences of their FMS waterpumps taking out their radiators and other horror stores due to the impeller shaft breaking off.
At this point, I tried to stop the JEGs order for the FMS pump, but it had already been shipped. On arrival, this new water pump already had corrosion starting on the back plate and it has not even been close to an engine. This will be returned. I am not impressed with the poor manufacturing quality. Dennis Olthoff said he's seen some made in Korea and others built in Canada. So quality must vary dramatically.
Based on recommendations from two other GT40 owners who are good friends, namely Jack Houpe and Mike Trusty, I decided to go with an electric water pump and called Meziere. Jack already has one on his car is is happy with it.
Told Meziere what I had and ordered a 55gpm unit that bolts onto the block. The plan was to not use a pulley on the front of it (they do supply models with an idler pulley) and just use a shorter alternator belt. Crank pulley direct to the alternator pulley.
I paid extra for overnight delivery and received the pump on Christmas Eve.
A beautiful unit... but the wrong one. It had no back plate and the hole pattern wasn't even close.
Sent it back to them with a gasket and pictures of the front of my engine. The holidays got in the way, but I hope to receive the replacement pump today or tomorrow. They claim I'm getting the right one. We'll see...
I plan to plug the two holes on the front cover with set screws and seal them if the new pump does not use them and also make sure the gasket is securely mounted/glued before bolting the pump on.
On the subject of electric water pumps, I have learned there are several advantages... Maybe others already knew this, but I'm just getting there.
a) You are supposed to gain 10 or so horsepower
b) You have full flow - all the time. Even at idle.
c) You can fill the system with the pump running and bleed the system completely without ever having to start the engine.
d) You can set the pump up with a delay relay and have it run for awhile after shutting down, thus minimizing heat soak effects.
I have quite a bit of experience with Ford big blocks and Clevelands. This is my first foray into Windsor land and I'm still learning.
Hope this is slightly useful from someone.
FWIW,
Kirby
I know what the hole is...
First a little background.
Ford decided to take a weird approach (as compared to the rest of the world) to sealing up their water pumps.
The earlier design (as opposed to the shorty late designs common to the Explorer and newer Mustang 50) has a steel plate that seals the back of the water pump.
That steel plate has only two areas that are to be sealed to the timing cover - the two large ports that pass the output of the water pump through to the front cover and ultimately the block.
If either of these two ports do not seal properly, the coolant will get between the steel plate and the timing cover. If not for the weep holes (probably used to detect leaks as well as relieve any air pressure changes in the chamber) - the coolant would build up in the chamber. This could ultimately cause the chamber to corrode and coolant to spill into the crankcase.
So - I believe that what you'll need to do is remove the water pump and replace the gasket that goes between the steel backer plate and the timing cover. Might be best to replace both gaskets.
Yes - Right Stuff.. No leaks..
