We had the lower half of the engine rebuilt by LN Engineering and assembled the top half. The "new" engine is now in the car and hooked up enough to turn the engine over with the starter (no ignition on purpose). All is good EXCEPT we are not making oil pressure. We have tried:
Priming the pump
Filling the oil cooler
Removing and inspecting the OPRV
Turning the engine over without the OPRV
The Crankshaft bolt has been torqued to 155 ft lbs
Based upon a Pelican Parts forum we have learned the Crankshaft Timing Gear for the Timing Belt may be installed in correctly. Videos of people installing this gear and the parts diagram are not consistent with respect to the correct orientation of this gear.
So, does the shoulder on the gear face the oil pump/engine or does it face the front of the car? Currently, the shoulder on this car is facing the front and we are not making pressure.
Thank you!
'86 951 No Oil Pressure
Sorry for the delay in getting back on the CarPokes forum; was traveling for about a week.
We have confirmed the correct installation of the Crankshaft Timing Gear is for the shoulder/flange to point to the front of the engine, thus away from the oil pump. We are looking for other sources of the problem. Will keep you posted on our progress.
We have confirmed the correct installation of the Crankshaft Timing Gear is for the shoulder/flange to point to the front of the engine, thus away from the oil pump. We are looking for other sources of the problem. Will keep you posted on our progress.
Randy Zwetzig
Fort Collins, CO
1986 951
2016 Cayenne Turbo
Fort Collins, CO
1986 951
2016 Cayenne Turbo
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walfreyydo
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The starter itself may not turn the engine over fast enough to build pressure. I had this happen on a previous subaru engine I rebuilt that would not build pressure until the car was actually started. Thats not much peace of mind to be sure but just wanted to share that experience.
Maybe others will have more specific information for the 944 engine and whether its expected or not to build pressure from the starter alone.
If the engine was built using assembly lube (I assume it was), then that may be sufficient to protect the engine during cranking/starting until pressure actually takes over. You may want to give LN engineering a call to get their perspective on this and lack of pressure using starter torque alone, but to me that is not overly surprising.
Maybe others will have more specific information for the 944 engine and whether its expected or not to build pressure from the starter alone.
If the engine was built using assembly lube (I assume it was), then that may be sufficient to protect the engine during cranking/starting until pressure actually takes over. You may want to give LN engineering a call to get their perspective on this and lack of pressure using starter torque alone, but to me that is not overly surprising.
Last edited by walfreyydo on Tue Jun 09, 2026 8:27 am, edited 1 time in total.
89 S2 Variocam, Megasquirt DIYPNP
Garage
Garage
When I cranked over my new engine a few months ago, I took out all the spark plugs so the engine would crank over faster. Even then it did take a little bit to see the oil pressure rise. 20 to 30 seconds. Was a little scary to sit there and crank on it for so long and not see oil pressure but I knew it had assembly lube so I kept on and it finally went up.
The starter alone with the plugs removed should be able to build oil pressure. Some people find they need to apply a small amount of pressure to the crankcase through the dipstick tube to help prime the pump, but I didn't.
I had a similar problem with a freshly rebuilt motor but in my case, I built pressure for a second and then it dropped and never came back. My issue wound up being a blown freeze plug - specifically the one at the bottom of a cylinder. It must have worked its way loose while the block was getting hot tanked or while it was being machined. The oil pump was just dumping the oil right back into the sump.
Image borrowed from another forum
Other issues could be the pickup tube being cracked, the wrong pickup tube seal, or the girdle having been installed without sealant but I doubt it - LN is pretty experienced.
Good luck!
I had a similar problem with a freshly rebuilt motor but in my case, I built pressure for a second and then it dropped and never came back. My issue wound up being a blown freeze plug - specifically the one at the bottom of a cylinder. It must have worked its way loose while the block was getting hot tanked or while it was being machined. The oil pump was just dumping the oil right back into the sump.
- img_20160805_184635362_030b268ec66ae52c8ef81647d12e00dcdb31ff7c.jpg (295.2 KiB) Viewed 38 times
Other issues could be the pickup tube being cracked, the wrong pickup tube seal, or the girdle having been installed without sealant but I doubt it - LN is pretty experienced.
Good luck!
- Patrick S.
1986 944 Turbo
2011 VW Touareg TDI
PCA Chicago Region
1986 944 Turbo
2011 VW Touareg TDI
PCA Chicago Region
A few years ago, I had a local racer call me in a panic. He had tried everything to make oil pressure and got nowhere. He asked me to stop by and help him out.
We did all the usual stuff, but no joy.
I finally determined that it must be the oil pump. We tore it down; it all looked perfect. We suspected something wrong with the pump.
Finally, we took apart the oil pump to look at the main gear in the pump. My friend had several pumps disassembled on the bench. We ultimately determined that he had used a gear from an early pump (82-85/1) in a late pump. When Porsche changed the pump to flow more oil, they made this gear about 10 mm thicker. Too much clearance, not oil pressure.
It taught me a lesson: don't assume that all the parts that look the same are the samee. Measure to be sure.
We did all the usual stuff, but no joy.
I finally determined that it must be the oil pump. We tore it down; it all looked perfect. We suspected something wrong with the pump.
Finally, we took apart the oil pump to look at the main gear in the pump. My friend had several pumps disassembled on the bench. We ultimately determined that he had used a gear from an early pump (82-85/1) in a late pump. When Porsche changed the pump to flow more oil, they made this gear about 10 mm thicker. Too much clearance, not oil pressure.
It taught me a lesson: don't assume that all the parts that look the same are the samee. Measure to be sure.