 Testing a motor: what should I do. |
|
|
|
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG.
This site is not affiliated with Porsche in any way. Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners. |
|
|
  |
| Cevan |
 Jun 12 2008, 09:22 AM
Post
#1
|
|
Senior Member  Group: Members Posts: 1,079 Joined: 11-December 06 From: Western Massachusetts Member No.: 7,351  |
I have recently come to purchase another 914 with a 2.0 motor. I am contemplating doing an engine swap, replacing my 76 hp 1.8 with a 95 hp 2.0. I originally wanted to build a 2056 (still do) but then this car came along. The car allegedly has 72,000 miles on it. I don't have much history on the car other than the fact that the PO bought the car in 2000 and the inspection sticker on the windshield is from 1994.
I want to assess the health of the motor and see if it makes sense to do the swap. What is the best way to do this? Leakdown test? Compression test? The motor does run, and I should be able to drive the car up and down my driveway (it's long) to warm it up. |
   |
 
|
| ChrisFoley |
Jun 12 2008, 10:01 AM
Post
#2
|
|
I am Tangerine Racing Group: Members Posts: 7,925 Joined: 29-January 03 From: Bolton, CT Member No.: 209 Region Association: None 
|
Leakdown test.
|
|
|
|
| SLITS |
Jun 12 2008, 10:07 AM
Post
#3
|
|
"This Utah shit is HARSH!" Group: Benefactors Posts: 13,602 Joined: 22-February 04 From: SoCal Mountains ... Member No.: 1,696 Region Association: None  |
Make sure the valves are adjusted correctly.
Do a quick compression test for a quick evaluation then do a leakdown for a final evaluation. The leakdown, as RC said, is the absolute best. |
|
|
|
| Cevan |
Jun 12 2008, 10:09 AM
Post
#4
|
|
Senior Member Group: Members Posts: 1,079 Joined: 11-December 06 From: Western Massachusetts Member No.: 7,351 |
I have neither tool, so can I just get a leakdown tester or should I get both? I've read that you should have a way to prevent the motor from spinning so that once you pressurize the chamber, it doesn't turn the motor over. How is this done?
Hey Chris, can I get a tour of your place sometime?? |
|
|
|
| SLITS |
Jun 12 2008, 10:17 AM
Post
#5
|
|
"This Utah shit is HARSH!" Group: Benefactors Posts: 13,602 Joined: 22-February 04 From: SoCal Mountains ... Member No.: 1,696 Region Association: None |
QUOTE(Cevan @ Jun 12 2008, 09:09 AM)  I have neither tool, so can I just get a leakdown tester or should I get both? I've read that you should have a way to prevent the motor from spinning so that once you pressurize the chamber, it doesn't turn the motor over. How is this done? Hey Chris, can I get a tour of your place sometime?? If it's on dead exact TDC on the cylinder, it won't generally turn over. That said, it is hard to get exact TDC (timing marks are approximate) so you have to lock it somehow ... wrench on the fan hub bolt head or on the alt pulley nut (and holding the fan belt) are about the only choices you have with the engine in the car. That's why I said a quick and dirty compression test first. |
|
|
|
| brer |
Jun 12 2008, 10:19 AM
Post
#6
|
|
Advanced Member Group: Members Posts: 2,555 Joined: 10-March 05 From: san diego Member No.: 3,736 Region Association: None |
sounds like a good topic for a "write up".
How to inspect and assess a motor in/out of a vehicle. |
|
|
|
| SLITS |
Jun 12 2008, 10:26 AM
Post
#7
|
|
"This Utah shit is HARSH!" Group: Benefactors Posts: 13,602 Joined: 22-February 04 From: SoCal Mountains ... Member No.: 1,696 Region Association: None |
A further note on Leak Down Testing came from the Pelican 911 Engine Rebuilding forum .... If the numbers are bad, try turning the engine a degree or so each side of the TDC "mark". If the numbers improve, you were not at true TDC anyway.
|
|
|
|
|
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:
|
Lo-Fi Version | Time is now: 15th May 2024 - 07:58 AM |
Invision Power Board
v9.1.4 © 2024 IPS, Inc.