Update notes to 2014 manual, 1200 – Crankcase group.


If you are the owner of a 2014 conversion manual, below are some short notes on the 1200 – Crankcase group section. I have written about these details in the last 3 years, but they are presented here in summary form, please update your manuals and notebooks accordingly:


2017 commentary: – This group is only slightly changed. Builders working on a 3.0L or 3.3L Corvair have always had to send their case to SPA to have it machined to fit the larger cylinders. In the last 3 years the Wesemans have also had to become experts in Corvair Head stud replacement options, as their “EIB” kit engines needed excellent head studs, and they also wanted to offer this to builders having their cases machined. If you are looking at a core case, and not looking forward to replacing some studs, call the Weseman’s at SPA, 904 626 7777, and they will be able to discuss the costs and options of head stud work.



Above, thirty-six 1964-69 Corvair Cases pictured on the patio between our hangar and house. They have since been moved to the SPA/Panther factory. If you are building an engine and your core case has a serious issue, read this story: Corvair Case sale, 36 available, $100 each.


1201-  Check to see the oil gallery plugs are reinstalled in the engine before assembly. We had at least two people forget this in 2016. You have to take a lot of the motor apart to fix this, and you will not see the mistake until the engine has no idle oil pressure on the run stand.

Do not over tighten the gallery plugs. they may have been very hard coming out, but the have a very low torque value, on the order of 10 to 15 foot pounds going back in. At least one guy a year cracks his case torqueing these like they were lug nuts on a dump truck.

Be advised that all replacement head studs need to be checked for strength before the rest of the motor is assembled. in 2015-2016, we has a rash of replacement head studs, made outside the US, that essentially had no heat treatment. They would never get to 25 foot pounds, the just kept stretching. If you have replacements in your engine read this: Testing Head Studs, note that it has been on my blog for 5-1/2 years.


1202- For people who like new hardware, the Weseman’s have grade 9 case bolts and nuts available.


1203- See 1202 above.


Thank you. Wewjr.


About William Wynne
I have been continuously building, testing and flying Corvair engines since 1989. Information, parts and components that we developed and tested are now flying on several hundred Corvair powered aircraft. I earned a Bachelor of Science in Professional Aeronautics and an A&P license from Embry-Riddle Aeronautical University, and have a proven 20 year track record of effectively teaching homebuilders how to create and fly their own Corvair powered planes. Much of this is chronicled at www.FlyCorvair.com and in more than 50 magazine articles.

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