With most engines if the case becomes pressurized leaks will be created where they previously did not exist. Its food for thought but the amount of pressure required to leak test a motor would surely cause some seal to blow out. The first thing that comes to mind would be a rear main seal. Chuck

I would highly recommend starting any Porsche engine on an enigne stand prior to puttin the thing back into the body.

Porsche is famous for "marking its terratory" with a bunch of spilled oil. No doubt a bunch of non Porsche owners will contest this fact, but its true, as any Real Porsche owner will testify.

Only a MB diesel is more well known for marking its territory.

I agree with Snowman. I posted here before I installed my rebuild and everyone said don't bother with a stand. In hindsight I should ahve done it.

now for the DIY'er do you suggest building a engine test stand? or are you talking about taking it to a reputable shop that has a stand and have it started there?

how much do shops charge for this service?

Do you run normal break in procedures while on the stand or once engine is in car?

just wondering...

I did everything else myself, by comparison the stand would have been easy.

It is standard practice on two strokes (or it is supposed to be) to pressure test the engine cases up to 5 psi.
When I do it I pressure it up and then shut off the air and start checking for leaks with snoop (soapy water). I also watch the gauge to see if the pressure falls off. No reason that couldn't be done with a 911 engine but I think it is overkill.
Dr. Deming taught us that inspection after the fact is too late, the time to inspect is while you still have time to change the outcome without starting over. Sorry, that just slipped out. Too much brainwashing in the 90's.

Running on an engine stand? A little easier if the engine wasn't a dry sump. Supreme overkill. Just install it in the car - you can't run in an engine on a stand, unless it's a dyno...

-Wayne

Its easy, just mount the oil tank next to the engine/transmission and run the std oil lines between them, you do not need the oil cooler connected. Its worth the small ammount of extra effort, given the ammount of time required to fix anything in the car.

wouldn't the torque of starting the motor need a sturdier stand? i don't trust that harbor freight stand with a 200hp engine vibrating away

plus you'd need a fuel hook up, oil, electrical

i'd say take it somewhere to run on an engine dyno (like jerry woods) can do some fine tuning while you are at it...

or install into car and cross your fingers

MJ

I think you are confusing "engine test stand" with "engine assembly stand".
A simple engine test stand would just support the motor+transmission or part of a transmission bell housing. Heck, you could probably just support it on some blocks if you weren't afraid of it vibrating off. The transmission is used to support the starter.
Seems like a lot of work compared to just popping it in a car but I suppose if you did a lot of motors it might be worth it.
I know a shop that has one. I've never seen it but I figured it what they had after a piece of it was left on a friend's motor that they debugged.
-Chris

I think the main benefit would be the ability to see where the inevitable oil leaks are. I had several small leaks that would have been easy to diagnose and fix on a test stand, but were difficult to troubleshoot with the engine in the car.

In the end I spent more time removing/installing several times, than I would have spent building a test stand and fixing everything at once. I'm sure this is less of an issue after you have done a couple of Porsche engines, and for those of you not doing 2.7's.

Then again, maybe I'm just a crappy mechanic.

Your mechanical skills are probably just fine. What you encountered is what most DIY Porsche engine builders encounter. Building a Porsche engine is not as easy as some would have you believe. Your ability to admit to the problems is admirable. Keep trying and you'll get it right sooner or later.

It's just a question of whether the engine mounting bolts wear out before my resolve :)

Its really no big deal, not matter the HP of the engine. They run very very smooth. Heck you can almost start them on the ground ( The only reason I wouldn't suggest this is the ammount of dirt you might stir up) Otherwise anything that will hold the engine will do.

Engine Test Stand
 

Building a test stand might be a bit overdone if you rebuild a engine only once. But if you do it more regularly you might certainly benefit from it.

We will test our rebuild 2.2 engine on the test stand of the Porsche specialist we do business with.
(For images of test stand see www.erpa.nl --> chapter "Revisie & Restauratie" )

Kind regards,

Sander

Just put it in.
If it works , you win. Running the engine on an engine stand takes just as much work as installing it in the car. If you have a problem, take it out. When you get a system in your head, you'll find it only takes an hour or so.
Most of the problems in a new engine will show up immediately. Some will take a little longer. if you put it in and drive it awhile you can fix all the problems at the same time.
Good luck