Oil Filter Bypass Hole,Plug Or Not Plug? - Team Camaro Tech
Engine General Engine Discussion.

 
LinkBack Thread Tools Display Modes
post #1 of 6 (permalink) Old Mar 15th, 03, 08:19 PM Thread Starter
 
Join Date: Feb 2003
Posts: 24
Post

Has anybody ever heard of removing the bypass spring and install a plug?I wish that I never did.On initial start up the hyd.roller cam 350 w/a m55a melling pump w/a short fram filter showed to have about 50psi.As the engine warmed up it slowly decreased to about 25psi and never really wanted to build upon increasing the rpm.But it did have oil pr.so I took off down the road.About 50 miles later it has about between 15 to 20psi at idle and only builds to a max.of maybe 25psi.I new there was a problem so I removed the plugged oil filter adapter and installed another one from another 350 that I had,and installed a new filter of the same kind.Problem is fixed.It was to my understanding that roller cam motors should plug the bypass hole,and the machinist I used agreed.Has anybody else ever experienced the same problem?If not I hope I can help somebody out that is thinking of doing this,and just dont do it.
2SLO4ME is offline  
Sponsored Links
Advertisement
 
post #2 of 6 (permalink) Old Mar 16th, 03, 03:40 AM
Senior Tech
 
Join Date: Feb 2001
Location: Concord Cal. USA
Posts: 2,664
Post

The filter isn't big enough. When you started it initually there is always going to stuff get trapped in the filter (moly etc.) and it partually plugged an already too small a filter. In one of Bill Jenkins books he stated that after much testing he came to the conclusion that even a small block Chev. must run the 2 quart truck filter to have enough flow with the bypass blocked. Leave it the way Chev designed it. You will have no problems.
oger is offline  
post #3 of 6 (permalink) Old Mar 16th, 03, 04:18 AM
Senior Tech
Mark
 
Join Date: Feb 2002
Location: LR AR
Posts: 2,372
Post

I do block them. Always have.

The molly paste assembly lube used for cam break in will plug the filter soon after you fired up the new engine. You should follow the directions regarding the cam break in procedure then change the oil and filter after about 1 hour while still warm. That gets the metal crud and molly paste out of there. The rings will not like the molly paste while trying to break them in so it needs to come out as soon as possible after the cam is broken it. After that, you should not have problems with low oil pressure. If it does affect your oil pressure after the first change, your oil was not being filtered anyway [img]graemlins/clonk.gif[/img]

Think about it another way. If you leave it alone you will still quickly plug the filter with the molly paste and the bypass will do its job and open. Now you are breaking in a brand spanking new engine using no oil filter at all. All those metal particles are just being pumped right back into the oiling system and continuously recirculated. That can't be good.

If you plug it, you will always have filterd oil. During the break-in process you may see lower pressure on the gauge but at least the oil is still getting filtered. After the initial oil change, you should not have low pressure issues any more. If you see low pressure on the gauge after the initial break-in, you need to check the filter as it may be dirty. If not, you have other problems. The engine is not under load during cam break in and the pressure is not in the danger zone.

Loose that Fram filter. They are not the best. Try a Wix or Purolator. They are much better.

Just my opinion. [img]smile.gif[/img] Your results may vary but I want you to have both sides of the story.

-Mark.
stingr69 is offline  
 
post #4 of 6 (permalink) Old Mar 16th, 03, 07:04 AM Thread Starter
 
Join Date: Feb 2003
Posts: 24
Post

I used the BG assembly lube when I assembled my motor which I could be wrong but I dont think it is a moly type lube.At least it doesnt appear to be,and the roller cam and lifters had already been broke in before.So I used the same assembly lube as the bearings when I installed it.And I lubed it real good.I cant use a larger filter because it hits the hooker comp.headers.I assume because the heads have been angle milled.So I guess I will try it again now that the break in oil is out and use maybe a different filter.I thought the fram filters was the best.Is there more opinions about the filters.And should I reposition the headers in your opinion to accept a larger filter?Thanks for the replys. [img]graemlins/sad.gif[/img]
2SLO4ME is offline  
post #5 of 6 (permalink) Old Mar 16th, 03, 07:10 AM
Retired
Jim
 
click's Avatar
 
Join Date: Jun 2001
Location: Central Minnesota
Posts: 15,978
Post

Here is some interesting reading on filters. The largest filter you can fit in is always better for the engine.
The Frams seem to be the cheapest to buy and not the best in filtration either. Follow what others are saying when they have the rollers, experience is better than an overhaul.

[img]graemlins/thumbsup.gif[/img]

http://www.scuderiaciriani.com/rx7/oil_filter_study/

Click..is Jim..former owner of a 69RS-LM1 350/255 - 700r
"There will come a time when you believe everything is finished,
That will be the beginning." Louis L'Amour
click is offline  
post #6 of 6 (permalink) Old Mar 16th, 03, 08:16 AM
Moderator
David Pozzi
 
davidpozzi's Avatar
 
Join Date: Nov 1999
Location: Central California, USA
Posts: 10,094
Post

Fram and others make a racing filter that is higher flow.
The higher flow is gained by using filtering media that is more porous. The disadvantage is they usually don't filter as fine a particle out.
David

[ 03-16-2003, 10:50 AM: Message edited by: davidpozzi ]

Check my web page for First Gen Camaro suspension info:
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

67 RS 327 original owner. 1965 Lola T-70
davidpozzi is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Team Camaro Tech forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address.
NOTE we receive a lot of registrations with bad email addresses. IF you do not receive your confirmation email you will not be able to post. contact support and we will try and help.
Be sure you enter a valid email address and check your spam folder as well.



Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may 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 Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome