Water Pump Vs Timing Cover Conflict

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dibbons

dibbons

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Sometimes the simplest procedures soon turn into a bigger deal than one could ever imagine.

This 318 was rebuilt by a "reputable" machine shop that had been in business for over 40 years (I am not placing the blame on this idiosyncrasy on anyone by the way). My mission was simply to repaint it and replace the oil pan while I was at it. So the motor has already been put together once, so what could go wrong doing some basic pre-assembly checks (like cleaning out the bolt holes and checking threads on fasteners)?

Trial fit of the same cast iron water pump using the three shortest bolts (one on center top and two on bottom across from one another). Well, I could not thread the bolt on top by hand, it would not even start if the other two bolts were started first. Starting the top bolt first, then the lower right bolt would not thread by hand. No problem in either case with the lower left bolt starting by hand. I jiggled and jiggled but nothing doing. I could see the top hole in the water pump was just ever so slightly too high and that was causing the problem (see foto #1).

The conflict between the timing cover machining and water pump manufacture was probably the fault of some minor quality control issue. I don't remember if the water pump was new or rebuilt and neither can I recall the origin of the timing cover (which has the built in timing marks).

Brought out my Dremel tool and a small cylindrical sanding attachment (coarse grit) and proceeded to elongate the top hole in the water pump. Problem solved (see foto #2). The machine shop got it put together 10 years ago without having performed this final step, lucky dogs.

water pump bolt 1.JPG


water pump bolt 2.JPG
 
Don't you have the wrong pump on that timing cover? AKA early pump / late timing cover?

That pump should have the timing marks on the pass side, and vice versa
 
67Dart273 said:
Don't you have the wrong pump on that timing cover? AKA early pump / late timing cover?

That pump should have the timing marks on the pass side, and vice versa
Click to expand...

Yeah, I believe you're right. Early pump, late cover.
 
Now's the time to make sure the balancer timing mark is in the right spot for that timing cover, or, if you have the early balancer, you also have the timing pointer for it. You can always remark the balancer if needed. sometimes it's hard to see the timing marks on the driver's side with your combination. Add power steering and it can be a real pain. When I build an engine, I always use a piston stop to verify the timing mark on the balancer lines up exactly on TDC. If not, it either gets replaced if I think the outer ring has slipped, or it gets remarked.
 
Since the timing marks are on the driver side that would be a late cover. Does you damper line up with that cover?
 
dibbons said:
Sometimes the simplest procedures soon turn into a bigger deal than one could ever imagine.

This 318 was rebuilt by a "reputable" machine shop that had been in business for over 40 years (I am not placing the blame on this idiosyncrasy on anyone by the way). My mission was simply to repaint it and replace the oil pan while I was at it. So the motor has already been put together once, so what could go wrong doing some basic pre-assembly checks (like cleaning out the bolt holes and checking threads on fasteners)?

Trial fit of the same cast iron water pump using the three shortest bolts (one on center top and two on bottom across from one another). Well, I could not thread the bolt on top by hand, it would not even start if the other two bolts were started first. Starting the top bolt first, then the lower right bolt would not thread by hand. No problem in either case with the lower left bolt starting by hand. I jiggled and jiggled but nothing doing. I could see the top hole in the water pump was just ever so slightly too high and that was causing the problem (see foto #1).

The conflict between the timing cover machining and water pump manufacture was probably the fault of some minor quality control issue. I don't remember if the water pump was new or rebuilt and neither can I recall the origin of the timing cover (which has the built in timing marks).

Brought out my Dremel tool and a small cylindrical sanding attachment (coarse grit) and proceeded to elongate the top hole in the water pump. Problem solved (see foto #2). The machine shop got it put together 10 years ago without having performed this final step, lucky dogs.

View attachment 1715594483

View attachment 1715594484
Click to expand...


Hey man, get rid of the bushings on the hose fittings and just get the proper hose fittings for the water pump... These will get you the proper hose nipple and the correct pipe thread to fit the water pump threads... It's much cleaner...


5/8" heater hose nipple with 3/8" pipe thread:

https://www.grainger.com/product/GR...itting-6AFH7?searchQuery=6AFH7&searchBar=true


1" hose nipple with 3/4" pipe thread:

The bypass hose will fit better with these also... Order 2 of these, one for the intake and one for the water pump to fit the 1" bypass hose from those years...

https://www.grainger.com/product/GR...itting-6AFJ5?searchQuery=6AFJ5&searchBar=true
 
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Is it possible the timing cover just has some corrosion/ rust/ debri/ old gasket down one or the other holes?

So far as the timing marks you can create a pass. side one easy. Get yourself or just make a pointer. It does not matter exactly where the pointer points as long as you have a clear view down the pass side.

Now use a piston stop to create a new TDC using the new pointer. Then measure around the balancer with a thin flex tape, and figure out "degrees per inch" and mark the balancer out to 50* or so. I used to do this by jacking up the car some, then laying under and looking up at it. Way easier than trying to get "straight" view at it from above, or pulling balancer
 
Water pumps and timing covers should be interchangeable on LA engines after about 67. I have swapped from steel (69 back) to aluminum (70 up) water pumps with no issue. Timing marks can be a pain on engine swaps.
 
same gasket on a 63 casting and a 68 casting....dead nuts on. My iron pump is on my 3rd 86 cover, no issues. I bevel the ends of those bolts to assist picking up the threads. Those bolts take some abuse as water jacket. Maybe that water pump is a replacement casting as mine has the threaded boss where your blank is.
(disregard the gaskets that are on backwards...Doh! :p)
20200913_192159.jpg
20200913_192132.jpg
 
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Possibly but the new one vs orig mopar, the boss thickness was thicker on the new one. It was a pain to get figured out. OP cant be bothered with the thanks button....so f it.
krazykuda said:
There's supposed to be a spacer on one of the triangular bracket holes because one boss sits lower than the rest...
Click to expand...
 
Make sure it still turns. Would hate to have it rocking on the impeller.
 
It already has 2,000 mile of run in on it. I'm am just putting it back on after painting it. I don't see any damage.
 
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Once upon a time... timing belt broke in my 96 Camry 4 cyl. i found a kit on ebay that included timing belt, water pump, tension idler, everything, for cheap. I had to use a rat tail file to elongate bolt holes in the water pump so it would mount in the right position. Wong the chinaman didn't mount this casting in the fixture properly.
 
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