Timing Cover information

[Ray Hamilton]

I've been through this once with the other 3.1 hybrid I built but my memory isn't good. I'm building another 3.1 out of an '89 Firebird 2.8 with serpentine belts. An early 2.8 water pump, or Fiero, which is where the engine is going, won't fit this timing cover. I know there's another out there that will fit cause I bought one off ebay when I built my last 3.1. The cover is the same as the one used on the crate 3.4's, #12509037/10049009. An early Camaro cover I believe is what I used before. I've got a line on an '87 Fiero cover that should work as Fiero's never had serp belts so the pump should always have been the same. Cover doesn't have the extended lip that bolts to the early pan that is different on the front for the same reason.
Am I right on the cover issue? The '89 cover won't work with the early pump. ?????

[60dgrzbelow0]

Does the Oil Pan on the engine you intend to build still have the angled (beveled or extended) front section from the original Oil Pan? Images of your lower front engine would be helpful to see exactly what is going on. If you intend to use the TC from a 93-95 L-32 3.4L V-6 Engine, you'll have to investigate if there is an oil pan available for your S10 that can accommodate this; one without the feature of having the pan protruding in front of the face of the engine block as on earlier 60* motors. If it is already shaped in front like the 3.4l engines in the Camaros and Firebirds ...so much the better. I'm unfamiliar with the Chevy Truck S-Series Engine layouts, hence my cautionary explanation. "betterthanyou" can give you all the dope on that truck you would ever need to know.

The other important consideration is the direction of the Water Flow "Swirl" casting pattern on the Water Pumps. When comparing the 2.8L to the 3.4L Water Pump casting "Swirl Patterns"... They are REVERSED...and consequently, you'll have to match the Water Pump you decide to use to whatever Timing Cover configuration you settle on using... it may not mount up at all if they do not match one another and even if they still do... your engine will not cool properly because the water flow will be interrupted instead of being properly guided internally. Having the TC with you (cleaned and dressed up, naturally) when you purchase the Water Pump will allow you to make a quick mate up comparison and ease your mind about the match up right at the Auto Parts counter.

FWIW... Attached are some images of a 93-95 F-Body (VIN "S") Timing Cover and Water Pump Installation along with Brand New 3.4L Water Pump images to use as a future reference to compare with yours. The Best Water-Proof, Gas Proof, Oil Proof, Pressure Proof and Leak Proof Thread Sealer for this unique PITA Job is: --== ARP Thread Sealer==-- (See attached image...)

[geoffinbc]

The shortest setup you can get with a RWD timing cover is the Camaro 3.4L water pump. It is a reverse rotation pump with a short nose that is nearly flush with the edge of the belt. It will not support a clutch fan but I think that is your goal.


If you need to use an old style pan then you need an 86 timing cover which had the old pan seal but used a serp belt for the water pump and supports the late model reverse rotation pumps.

But the old pan seal does suck and the new 1 piece neoprene seals are much better and showed up in 87 on the S-10's the Camaro pans of the same era also bolt up. Gen II pans from FWD cars will also do the trick.

[Ray Hamilton]

I'm just trying to find a pan like I used on my last 3.1 build, #12509037/10049009, I don't know what it came off of, but it wasn't brand new. No pan extension and the ability to use the early pump. I was thinking the cover on my donor '89 Firebird 2.8 would work but the early pump won't even bolt up to it. It's also shallower, the early impeller hits the inside of the cover.

60dgrz, does the later pump actually run a different direction or is it just the cover that changes the direction of the flow?
Betterthanyou, could I use the '89 Firebird cover with a Firebird pump on my Fiero?

[60dgrzbelow0]

I'm just trying to find a pan like I used on my last 3.1 build, #12509037/10049009...

Ray...

The attached image is of your 2.8L to 3.1L Engine Conversion/Upgrade (I Glommed from Your Profile Data)... Is THAT the Oil Pan you mean? Do you have other images of this build on the same engine stand that highlight its appearance and make for an easier identification of what the Oil Pan on this motor came from?

60dgrz, does the later pump actually run a different direction or is it just the cover that changes the direction of the flow? Betterthanyou, could I use the '89 Firebird cover with a Firebird pump on my Fiero?

I think that the Timing Cover and Water Pump inner design is match reversed and so is the direction the water passes through the block. But it should not make any difference as long as both the components are a match in guiding the water flow...its still going to circulate through the engine block and back into radiator in the proper manner. The direction of any fluid movement is contingent on whether the inflow and outflow ports are either above or below the center-line of the impeller's standard "One Way Only" Direction of Rotation...NOT that the impeller is actually turning in the opposite direction; although you could make the pump axially move in this "opposite" way, depending upon which side of the Serpentine Water Pump Drive Pulley the belt is introduced. But... without the "cupped" sides of the impeller blades facing the direction of rotation...very little water would be circulated through the engine block. If you notice the design of the inner channels...they become more and more narrow in the direction of the flow...and because liquids are incompressible...the water is channeled more and more against the rotating impeller blades...adding to the water pressure in the moving column of the coolant and speeding the cooler radiator water back through the engine block. Please forgive the overly complicated explanation...But that about covers the Fluid Dynamics involved.

[Ray Hamilton]

The engine pictured has an '87 S10 pan and a #12509037 cover and '86 water pump. I dug through my records of when I bought the cover and it was supposedly from an 84 to 86 Camaro or Firebird. It does not have the extended pan.
What you said about the cover and the pump matching is what I was thinking. As long as the length of the pump, as Betterthanyou stated, is of the acceptable length it should work OK in the Fiero as it doesn't have a fan on the engine. So my '89 Firebird engine swap doesn't have the same needs as far as the cover goes, as my '86 Blazer did. So I don't need a different cover as long as I use a pump designed for the '89 engine.

By the way, thanks to you both.

[geoffinbc]

Then you must run serpentine belts in order to have the correct reverse rotation on the pump.

And I wrote the 86 cover thing backwards. The cover uses the late model oil pan seal but uses the standard rotation pump. Sorry about that. The crate engine cover is the same thing. It was used so GM could have the better pan seal but keep the standard water pump so people could swap it into their 82 to 85 S-10 which still had V belts