 Stumped, Low Compression |
|
|
|
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. |
|
|
| AKJammer |
 Sep 7 2016, 09:04 PM
Post
#1
|
|
Newbie  Group: Members Posts: 6 Joined: 19-July 15 From: Alaska Member No.: 18,971 Region Association: Pacific Northwest  |
Engine: 1.8 1974.
I tore down the engine to replace Dead gaskets and seals. Purchased new jugs and pistons reassembled the engine. Fired it up and have 90 lbs of compression on 3-4 125 on 1-2. Completed a leak down test and all is good as it is holding what compression there is... Tore the engine down again and measured the cc of the heads and they are all the same. Part number 021.101.371S on both heads. Measured the deck height of the pistons at TDC and they are all the same.... Head gasket shims are all the same. What am I missing??? Thanks Jammer! |
   |
 
|
  |
Replies
| VaccaRabite |
Sep 8 2016, 07:57 AM
Post
#2
|
|
En Garde! Group: Admin Posts: 13,728 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region 
|
Compression on a fresh top end-er builds as the rings seat.
So assuming you cut your ring gaps correctly... Here is how I was taught to break in a fresh motor. Warm it up. When at operating temp, on your favorite quiet road, put the car in second gear and STOMP ON IT. All the way up the rev range. Then foot off and let the car engine brake back down (keeping the car in second gear). Do that two more times. Your rings should now be seated, and compression should be around 140-160 or so. Zach |
|
|
|
Posts in this topic
AKJammer Stumped Sep 7 2016, 09:04 PM
rgalla9146 Fuel injection or carbs ?
If carbs, were the ca... Sep 7 2016, 09:14 PM
AKJammer
Fuel injection or carbs ?
If carbs, were the c... Sep 7 2016, 09:19 PM rgalla9146
Fuel injection or carbs ?
If carbs, were the ... Sep 8 2016, 05:42 AM Root_Werks
[quote name='AKJammer' post='2395384' date='Sep 7... Sep 8 2016, 12:15 PM AKJammer
[quote name='AKJammer' post='2395384' date='Sep ... Sep 8 2016, 01:07 PM injunmort ring gap, ring stagger, valve seats, valve clearan... Sep 7 2016, 10:29 PM AKJammer
ring gap, ring stagger, valve seats, valve cleara... Sep 7 2016, 10:46 PM wndsrfr
ring gap, ring stagger, valve seats, valve clear... Sep 8 2016, 05:27 AM stugray
Rings haven't seated.....drive it like you st... Sep 8 2016, 05:49 AM The Cabinetmaker Sounds like an aka problem Sep 8 2016, 06:00 AM injunmort if it were mine and it is out and apart. i would d... Sep 8 2016, 07:58 AM AKJammer Thanks All! I have some Ideas of what to do n... Sep 8 2016, 12:10 PM r_towle You may want to check to make sure the case is fla... Sep 8 2016, 07:05 PM Root_Werks Also noting you stated 3-4 "side" doesn... Sep 9 2016, 10:18 AM old dog Just a thought.... Is the cam timing correct ? Goo... Sep 9 2016, 08:54 PM rgalla9146
Just a thought.... Is the cam timing correct ? Go... Sep 10 2016, 04:03 AM |
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:
|
Lo-Fi Version | Time is now: 9th May 2025 - 12:58 PM |
Invision Power Board
v9.1.4 © 2025 IPS, Inc.