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Discussion Starter #1
So I'm still trying to build this god damn Bronco. It's an 86, with a swapped in 302.

I got it because it was cheap. It was cheap because it was dumping coolant out of a freeze plug. Of course, the deeper I got, the more PO fuckery I found. The issue is overheat at idle. Let it idle, and after 4-5 minutes the temp just starts climbing.



Here is a quick run down:

--Build fan shroud (none present), install cheapo temp gauge in intake manifold (factory inop). I notice radiator only heats in certain areas >>> plugged with stop leak

--Flush radiator (x2, off vehicle), install t-stat (deleted by PFO). Still overheats.

-Replace clogged, single core radiator with new two core. Still overheats. Bubbles noted at radiator inlet. Gas analyzer shows HC levels rising in radiator at idle.

--Replace head gaskets. Straight edge & visual on block and head appear ok. Water pump impeller isn't awesome (small rust hole), so I replace water pump. Here is where it gets tricky.

The engine in my truck seems to be a carbed 302 (cam driven fuel pump), with a serp belt.

80-86 water pump doesn't match what is on the engine, so I get an 87+ pump. We (by this point I have called in friends smarted than myself) notice two things with this (later) pump:

**Impellers look backwards (maybe thats the original issue? serp belt coversion spinning original pump backwards?)

**Water ports/back plate do not match.





So we mix and match backing plates to try and make it work. Still overheats at idle. With new rad, tstat, head gaskets and new waterpump. By this time it's pretty late. I tried to sniff the radiator again, but it was inconclusive (HC in and out of rad, likely exhaust). I did a combustion leak test (blue fluid) and it came up negative.

I need to pull #s off the engine, but I'm getting discouraged here.





Would the wrong water pump cause over heat at idle? If so,
Would a small rust hole on the correct water pump also cause over heat at idle?
What other application uses a small body water pump? The pump on my bastard engine is the same size as an 87 Bronco 302, but different impeller and port configuration. What could it be from?

I guess this is my main question. I'd like to try this pump.

Or, am I missing something else?

:beer: for reading my babble.
 

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Post up some pics, but yes, there are normal and reverse water pumps for fords.
 

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Discussion Starter #5
So I checked a belt routing diagram for the pump I have, and it matches my set up. (And both are serp belt). So im thinking this pump is turning the right way but the ports are off, no?

I sniffed it again at lunch, and its registering HCs in the radiator still. That is not a good thing, right¿
 

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The timing covers are different for standard and reverse water pumps. All the mechanical fuel pump covers are for the standard rotation water pump. The water ports are in the same general location, but shaped different.

 

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Look at the pump for a 88 Mustang with a 302. I believe that is the year. It is reverse rotation with the standard rotation bolt pattern.
 

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FoMoCo MoFo
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5.0 Crown vics were a serp belt but standard rotation. They also used a small body aluminum pump in later years. What is the serp routing on this engine, and what timing cover is on it?
 

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FoMoCo MoFo
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You need a timing cover for your reverse rotation serp belt setup and water pump.
 

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Discussion Starter #11
You need a timing cover for your reverse rotation serp belt setup and water pump.
Why would that matter? Ports are in the same position, impeller is in the same position? The only difference is the impeller fins, and as long as they match the rotation they're being spun I can't see the difference.
 

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The ports on the reverse rotation cover are in a different orientation than the standard rotation cover. If you can find the correct pump it will have the standard rotation orientation but the impeller will be shaped to spin backwards compared to a V-belt setup.
 
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