Fuel pump ID

[Harmon C.]

I have a A/C fuel pump # 212 40658 stamped on the flange wil it work on a 71 LT1?

[Joe L.]

Re: Fuel pump ID

I have a A/C fuel pump # 212 40658 stamped on the flange wil it work on a 71 LT1?

Lyle-----

The AC 40658 fuel pump is the pump originally used on 1968-69 Corvettes with small block. It was only available in GM SERVICE for a very short time but was available through AC Delco for a longer period. It was replaced for GM SERVICE by the AC 40709. The 40709 is the pump used in PRODUCTION for 1970-71 LT-1 (and SERVICE for 1972 LT-1). The primary difference between the 40658 and the 40709 is the inlet chamber. The 40658 has a short inlet chamber; the 40709 has a long inlet chamber. We know the 40709 is compatible with applications originally using the 40658 because GM said so. We don't know, for sure, if the 40658 is forward compatible with applications originally using the 40709. However, I believe it is.

[Harmon C.]

Re: Fuel pump ID

Thanks Joe I know the inlet and outlet position is correct.

[David L.]

Re: Fuel pump ID

Lyle,

AC 40658 = GM # 6417337
AC 40709 = GM # 6470110

As per Chevrolet Parts History GM # 6417337 was discontinued in Aug. 1971 and replaced by GM # 6470110 which was discontinued in Aug. 1985.

Back in Jan. 1994 I bought 4 unboxed NOS 40658 fuel pumps (all stamped "40658) at the Cypress Gardens swap meet....all 4 for $20. Even though all 4 were NOS the coatings on the top part of each one of them had deteriorated (oxidation?) so that is why they were cheap.

When I bought my 1966 Corvette in 1979 the fuel pump on the non-original engine was stamped "DI 40658" where "DI" = April 1969.

Dave

[Joe L.]

Re: Fuel pump ID

Thanks Joe I know the inlet and outlet position is correct.

Lyle------


Yes, the inlet and outlet position is correct. The outlet position is, of course, critical if the original fuel line is to be used. The inlet position might not be exactly the same but it will work with no problem. However, the inlet nipple is higher on the 40658 due to the short inlet valve chamber.

[Ron G.]

Re: Fuel pump ID

The inlet at the bottom of the pump faces towards the left rear wheel. The later over the counter #40709 inlet faces towards the right rear wheel. It will still work just fine. - Ron