[vegasjones]

Hi all. I just put a 396 in my 65 Chevelle. Unfortunately I'm having cooling issues. What I'm curious about is how I can tell whether or not the block calls for a reverse flow water pump. I suspect it doesn't but I want to make sure. The casting number on the block is 3969854. Based on the years/models of cars/trucks this was put in I've seen options for both directions of flow. Can anyone point me in the right direction here with the water pump?

If it helps at all the pump I have is a brand new (not reman'd) pump and the manufacturer number for the pump is 130-2981. I purchased it from Carquest. If anyone can tell me if I'm running the correct water pump I'd greatly appreciate it.

I'm trying to narrow down the culprits to my cooling frustration.

 

[novaderrik]

every big block uses a standard flow water pump- the water comes in from the lower radiator hose and gets pumped into the block... then it goes up into the heads, to the intake, and back out to the radiator..

now that i answered the question you asked, i'll answer the question you meant to ask:

some water pumps are reverse rotation- the pump spins the opposite direction as the crank, but all blocks have the same water pump mounting provisions.... but these reverse rotation pumps were only used starting in '88 or so, and have a wide flat belt, with the smooth pulley getting spun by the flat part of the belt.. they don't have the bosses cast in and tapped for the alternator and power steering pump mounting points.. i don't know about the big blocks, but the small block reverse rotation pumps use 8mm metric fan mounting bolts and have a different bolt pattern for the fan than the earlier standard rotation pumps, which have 5/16" tapped holes..
so to summarize: if you have a v belt setup- or a setup from the 80's that spins the water pump and alternator the same direction as the crank with a wide flat belt- then you need a standard rotation pump that has the alternator and PS pump mounting provisions... if you have a flat serpentine belt that runs the pump opposite the crank, then you need one that doesn't have the mounting lugs on it...

 

[vegasjones]

That's perfect. I knew that this pump was a standard rotation, that's the thing I was certain of. What I wasn't certain of which you answered was whether or not the block called for a standard rotation pump. Since the block was from the late 60s early 70s your info that reverse rotation pumps didn't come out until the late 80s helps a lot.

Now that I've got that out of the way I'm off t search the forum for help with my cooling problem.

Thanks again.

 

[novaderrik]

what is your cooling problem?
what is your radiator/fan/shroud setup?
where is your ignition timing set, and are you running the vacuum advance to a full manifold vacuum or ported vacuum source?

 

[vegasjones]

I had a good friend of mine who is a long time Chevy mechanic do all the work so I'll answer the best I can.

I believe I've got a water flow problem which makes me believe its the pump. The car just heats up to around 220-230 after a bit of driving, stays there and won't cool back down much. Tonight it's a rather cool summer night for Vegas and it got up to 220 cruising around. On the freeway it dropped maybe 5 degrees. I checked the head gaskets today with a block test and all was fine. Just wanted to rule that out right away.

I've got a brand new aluminum 3 row radiator with a flexalite dual fan setup that has a full shroud that covers the entire radiator horizontally and nearly all of the radiator vertically. I'm fairly certain I'm getting proper airflow with the fans I have.

I was running a 180 stat but since that wasnt cutting it I put in a Moroso water flow restrictor tonight to see how that worked out. Still ran hot.

Total timing is at 36 degrees according to the mechanic who set it.

I'm not sure about the vaccuum advance to be honest with you. I'm not even sure where to look for this.

 

[novaderrik]

got any pics?

where is the temp gauge hooked up? what kind of a gauge- what brand, mechanical or electric?

 

[OLDED]

The initial timing set too low will cause the temp to be high. If it has any cam other than the stock one - it will need 16/18 degrees of initial timing set at the slowest idle possible with the vac. advance plugged. Then set the total by adjusting the weight' travel range. The shroud needs to cover the entire radiator with as little air leakage as possible. A 66 radiator works better that the original design 65 radiator as the 66 forces the entire width of the radiator to circulate the hot return coolant from the engine. The top hose enters the radiator tank on the driver's side on the 66 while the 65 rad. enters on the pass. side allowing the radiator to "short circuit" the water flow. I run that exact 66 BBC radiator and shroud set up in my 65 shown here with NO temp. issues - stock water pump. The 66 rad. and shroud are direct bolt in to the 65 radiator support. FWIW, Good luck with it, Ed

 

[vegasjones]

I can take pics of anything you'd like, just let me know what you'd like pics of. I've got it at work with me today.

The temp basically just climbs and climbs, even on the freeway, and never comes back down. It gets up to about 220-230. Not sure if it will keep climbing as I usually shut it down around that point.

I've checked the head gaskets by doing a block test through the radiator. All was fine there.

I asked my mechanic buddy who set the timing about it since I thought that might be a culprit and he said the timing is definitely right.

Over the weekend we discovered we were using too small of a pulley on the water pump (around 4 1/2 inches, not sure where it came from) so I put a bigger pulley on the pump (a little bigger than 6 inches) since we thought it was maybe moving the water too fast but that didn't help. So now the crank pulley is 7 1/4 and the water pump pulley is a bit bigger than 6 inches. That didn't work.

Again, the radiator is brand spankin' new. It's a 3 row aluminum built by Champion Cooling. I've got a brand new Stant 16lb. radiator cap. I had a Stant 180 stat in it until last night I put a restrictor plate in there to see if that would slow the flow and keep water in the radiator longer. The water pump is brand new, not re-man'd.

The lower hose has springs in it so it's definitely not collapsing.

Was far as water, I've got a gallon of coolant, 2 bottles of water wetter and the rest is distilled water. Is it possible I need more coolant? I was under the impression water should do just fine at dissipating the heat in the radiator.

I'm stumped.

 

[LeoP]

Even though your mechanic said the timing is right, get the number for the initial timing setting and post it here. I believe the above posts are on to something. good luck.

 

[vegasjones]

Here's the radiator I'm using minus the fans: http://www.ebay.com/itm/140956768372?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

Here are the fans I'm using: http://automotive.flex-a-lite.com/d...an-with-adjustable-thermostat-controller.html

 

[vegasjones]

Ok, he set the timing at 12 initial and 36 total.

 

[vegasjones]

And yes, it does have a cam. Here's the cam it has: http://www.summitracing.com/parts/CCA-K11-208-3

So with the post above it sounds like I do need to advance the timing.

 

[vegasjones]

Oh, and there is actually no vacuum advance on the distributor.