rb20det wacky compression? - Skyline Owners Forum

Welcome to the SkylineOwners.Com website. We aim to provide you with the largest knowledgebase anywhere on the internet for the Nissan Skyline.


Go Back   Skyline Owners Forum > Skyline Torque > General


General Skyline related chat only please
Sponsored By: www.OnlineCarParts.co.uk

Reply
 
LinkBack Thread Tools Rate Thread
Old 04-01-2018, 01:15 PM   #1
Registered User
 
Join Date: Jan 2018
Posts: 5
Club ID#: 87138


Trade Feedback: (0)


View My Pictures
Cool rb20det wacky compression?

Hey guys

Just looking for some opinions on a wet and dry compression test I did on my rb20det, note i did this when the engine was completely cold. Dry test I got around 75psi on all cylinders so I expected with a wet test for it to go up. wet test showed around 78psi on all cylinders.

Does anyone know why I could be getting such even low readings? perhaps its the compression tester? Thanks in advance
andoreniel is offline   Reply With Quote Share on facebook
Sponsored Links
Advertisement
 
Old 04-01-2018, 02:08 PM   #2
Super Moderator
 
Tricky-Ricky's Avatar
 
Drives: Skyline 350GT 6 speed
Join Date: Oct 2005
Location: Norfolk
Posts: 8,931
Club ID#: 5836


Trade Feedback: (1)


View My Pictures
Could well be that the valve seal is not good, try the test again with the engine warm and see what you get, I would presume you are keeping the throttle wide open and turning over the engine at least 6 times for each cylinder with a fully charged battery?
__________________
Pedants are men who would appear to be learned, without the necessary ingredient of knowledge.
- George Bancroft

Originally posted The Great White

"Nissan is like Lego"
Tricky-Ricky is offline   Reply With Quote
Old 04-01-2018, 09:13 PM   #3
Registered User
 
Join Date: Jan 2018
Posts: 5
Club ID#: 87138


Trade Feedback: (0)


View My Pictures
thanks for reply

Ill give a warm test a go today then, Yup throttle hard on, cranking about 5-6 times and fully charged battery.
andoreniel is offline   Reply With Quote
Old 09-01-2018, 10:18 AM   #4
Registered User
 
Join Date: Jan 2018
Posts: 5
Club ID#: 87138


Trade Feedback: (0)


View My Pictures
Unhappy

Just replaced all of the turbo set up and that's taken a few days hence me taking so long to reply. So here are all the stats of my compression tests--> These were cold, Dry-76,76,77,76,70,76 Wet all around 78. These were with a warm engine, Dry-77,75,80,75,78,76. Wet, 87,80,90,78,80,80. I noticed fresh oil on spark plug 1 and 3 when pulled out of warm engine and also cylinder 3 was smoking heavily. One would probably assume from this the whole engine is pretty worn-out?
andoreniel is offline   Reply With Quote
Old 09-01-2018, 10:25 AM   #5
Registered User
 
Join Date: Jan 2018
Posts: 5
Club ID#: 87138


Trade Feedback: (0)


View My Pictures
Also It smokes ALOT. at idle it is usually okay and doesn't have much visible smoke but with any revving it just billows smoke out. this could be due to valves as well?
andoreniel is offline   Reply With Quote
Old 09-01-2018, 11:27 AM   #6
Super Moderator
 
Tricky-Ricky's Avatar
 
Drives: Skyline 350GT 6 speed
Join Date: Oct 2005
Location: Norfolk
Posts: 8,931
Club ID#: 5836


Trade Feedback: (1)


View My Pictures
Sounds like it needs a good rebuild, the std figures should be about 100PSI higher than that,
and by those figures, the valve seal is not a big problem, personally, i would either give the whole motor a refresh and forge if you're going for more power.
__________________
Pedants are men who would appear to be learned, without the necessary ingredient of knowledge.
- George Bancroft

Originally posted The Great White

"Nissan is like Lego"
Tricky-Ricky is offline   Reply With Quote
Old 10-01-2018, 09:39 AM   #7
Registered User
 
Join Date: Jan 2018
Posts: 5
Club ID#: 87138


Trade Feedback: (0)


View My Pictures
Thanks for the input Tricky-Ricky, Ive sourced a new long block not yet looking for more power just a road legal rb that doesn't spit clouds
andoreniel is offline   Reply With Quote
Reply

Bookmarks

Tags
compression, r33, rb20det


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT +1. The time now is 05:22 AM.


Powered by vBulletin®
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.1
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
Copyright ©2002 - 2019, Verticalscope Inc.