Episode 31 - 1986 Porsche 944 Turbo Restoration - Engine Balance Shafts, water/oil pump

[@porsche944turbo]

Russ, There should be four studs on the front of the engine for mounting the waterpump.

[@EuropeanAutoCraftStudios]

Oh wait! Your right! The studs are missing.... Great catch, thank you.

[@jvaubry]

Russ, great video, thanks. On my 1988 early production 951, the gusset on the accessory drive for the. lower balance shaft has 4 bolts, 2 into the block and 2 into the accessory drive. Can’t explain why you have a 3 bolt gusset and an accessory drive from a later engine. As discussed in Rennlist and Clark’s garage, a stock 2.5 liter engine that is stroked with a crank from the 3.0 liter 944S2 and uses 100.5 mm diameter pistons results in a displacement of 2.8 liters. This configuration uses a Mahle piston with an offset wrist pin and either forged carillo or forged pauter rods. If the displacement is 2.7, perhaps only the bore was increased to achieve a 2.7 liter displacement. Otherwise you can check what pistons and connecting rods you have in the engine to see if it is a 2.8 liter displacement. I went the route of using the 3.0 liter crank, 100.5 mm Mahle pistons with the offset wrist pin, and Pauter rods for a 2.8 liter displacement. I was lucky in that I found a new old stock 3.0 liter crank on eBay for $1700.0, normally that crank new retailed for $3000.0!

[@EuropeanAutoCraftStudios]

I'm not sure what I'm for here, I'm soaking that #1 piston. I hope it moves so I can get a stroke reading. I'm pretty sure the cylinder will have damage. As always, your input is greatly appreciated. You have far more knowledge about these engines than I do. I'll be consulting you when it's time for planning this build. I think we will be mostly mild.

[@jvaubry]

@@EuropeanAutoCraftStudios Russ, respectfully, I am sure your knowledge of these engines far exceeds mine. Porsche made a 2.7 liter displacement engine in 1989 only, it had the same crank as the 2.5 liter(78 mm stroke), but was bored to 104 mm. The 3.0 liter engine has a stroke of 88 mm and a bore of 104 mm. The 2.8 liter is essentially a bore of 100.5 (0.5 mm oversized from the 2.5 l factory bore) and a stroke of 88 mm when using the crank from the 3.0 l block. So, if your engine is stroked, it is most likely a 2.8, unless the bore is 100 mm(2.5l factory bore), then it will be slightly less. If the displacement is 2.7l, it is not a stroked engine, just over bored, and measuring the bore would clarify that. Removing a piston and connecting rod would also clarify whether the engine is stroked, without having to measure the stroke length directly.

[@JVR_Funwithdesign]

The gear for the crank was mounted backwards, the lip should face outwards to prevent the belt from walking forwards. That's why it was too far back and the lip was eating away at the cover.

[@EuropeanAutoCraftStudios]

Ah ha! Thank you! It's been so long since I have done one of these. I went to school for these engines in 1984. I have worked on a lot of them since, but I sometimes miss things like this. Keep the knowledge coming, I really appreciate it!

[@JVR_Funwithdesign]

@@EuropeanAutoCraftStudios There's so many ways all the people who have touched this over the decades can have messed things up, it'll be great when it's all back together better than new.

[@jeffhammond8969]

Russ, great progress! Any chance that there is lateral play in the crank that caused the cover to get worn away?

[@EuropeanAutoCraftStudios]

Very good possibility, I'll check that after I get the connecting rods and pistons out. Good thought there Jeff.