61 283 FI oil pump, adapter, pickup id

[Joe M.]

A 1961, 283 is being built with KB166 domed pistons, 461 heads with 1.94 intakes, 097 cam with fuel injection, old style flat windage tray and baffled pan.

I have a collection of oil pumps, pick ups and adapters and not sure which to use. All my pumps have a top and bottom casting number 3732796 and 3704180.

The bypass adapters are from GM and AC.

Which combination of pump, pickup and adapter would be appropriate for this engine?

Identify original use for each pickup, adapter and pump?

[Wayne L.]

Re: 61 283 FI oil pump, adapter, pickup id

Joe-I would use the GM adaptor, although either should work fine.
I would use the 1.5" pick-up. The trick is to have it lay almost flat on the bottom of the pan, within an 1/8" or so. I usually tilt the pick-up upwards (engine upside down), and push it down with the pan to the block without gaskets. When you put in the pan gaskets, the pick-up will be up off the floor of the pan just a bit.
Either pump should be okay. Wayne

[Mike M.]

Re: 61 283 FI oil pump, adapter, pickup id

weld pickup to pump. mike

[Joe L.]

Re: 61 283 FI oil pump, adapter, pickup id

A 1961, 283 is being built with KB166 domed pistons, 461 heads with 1.94 intakes, 097 cam with fuel injection, old style flat windage tray and baffled pan.

I have a collection of oil pumps, pick ups and adapters and not sure which to use. All my pumps have a top and bottom casting number 3732796 and 3704180.

The bypass adapters are from GM and AC.

Which combination of pump, pickup and adapter would be appropriate for this engine?

Identify original use for each pickup, adapter and pump?

Joe-----


I think that either of the oil pumps will work ok. However, you want to be sure that the internals are ok if they are used pumps. If there's any doubt about the internals, I'd just use a new pump. Oil pumps are not very expensive and I always prefer the new pump "route". You also want to be sure that it has the correct oil pump relief spring installed, either high pressure or standard pressure. I'd go with the standard pressure for your application. Both of the pumps pictured are standard volume pumps and that's what you want.

As far as the pick-up goes, the one you need is GM #3764113, but it's discontinued. Easily available in the aftermarket, though. You can use your existing pick-ups IF they have not been previously installed and removed. The interference fit is lost once an oil pump screen is installed and removed. So, such a pick-up is no longer suitable for re-installation UNLESS you tack weld or braze the pick-up to the pump.

The collar-to-apex-of-curve dimension I get on an NOS GM #3764113 pick-up is 2.25" which is different from any of the dimensions you show. However, I expect that one of your pick-ups is correct; just a measurement difference. It's hard to precisely measure this dimension. The 3764113 does measure 1.5" from the bottom of the screen to the bottom of the pipe insertion surface, so that lets out your #4. Photos of an NOS GM #3764113 are provided below.

As far as the adapter goes, if you intend to use the original canister-style filter, you want to use the adapter embossed 5573842. This is GM PART #5573979 and that's what you need. I think the other adapter you have is designed for using a canister-style filter on a block designed for a spin-on filter. These were used for some 1969+ truck applications. I don't think it will fit, at all, on your block.

[Joe M.]

Re: 61 283 FI oil pump, adapter, pickup id

Thanks for your input!

What are some of the parameters to check when evaluating an oil pump for servicability?

thanks,
Joe

[Joe L.]

Re: 61 283 FI oil pump, adapter, pickup id

Thanks for your input!

What are some of the parameters to check when evaluating an oil pump for servicability?

thanks,
Joe

1) Scoring of the pump gears;

2) Scoring of the machined gear cavities in the pump body;

3) Excessive clearance between the end of the gears and the pump cover (should be about 0.002" to 0.007");

4) Excessive scoring or wear on the pump cover.