TheAMCForum.com Homepage
Forum Home Forum Home > The Garage > AMC V8 Engine Repair and Modifications
  New Posts New Posts RSS Feed - 401 100+ psi much oil pressure
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Click for TheAMCForum Rules / Click for PDF version of Forum Rules
Your donations help keep this valuable resource free and growing. Thank you.

401 100+ psi much oil pressure

 Post Reply Post Reply Page  <12345 6>
Author
Message
Boris Badanov View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Dec/14/2013
Location: NH USA
Status: Offline
Points: 4209
Post Options Post Options   Thanks (0) Thanks(0)   Quote Boris Badanov Quote  Post ReplyReply Direct Link To This Post Posted: Oct/21/2017 at 12:06pm
That's why I went to a couple of custom caps to swap around
to play with pressure on the Harley.

All this is custom, the external cam support plate
and the adjuster(S).

A drop or two of oil may not bother a guy with an old Rambler.
But Harley owners tent to be anal to an extreme about the
polish and look of the bikes.
Gremlin Dreams
Back to Top
Hurst390 View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Apr/20/2008
Location: secret
Status: Offline
Points: 5752
Post Options Post Options   Thanks (0) Thanks(0)   Quote Hurst390 Quote  Post ReplyReply Direct Link To This Post Posted: Oct/21/2017 at 1:37pm
Originally posted by Red Devil Red Devil wrote:

He wasn't getting over 45psi until he installed an adjustable relief valve.  

Your telling me 45psi is the norm on an AMC v-8?
SC/Hurst Rambler

11.62 120

100% Street Legal
Back to Top
Red Devil View Drop Down
AMC Addicted
AMC Addicted


Joined: Jul/10/2007
Location: Canada
Status: Offline
Points: 1743
Post Options Post Options   Thanks (0) Thanks(0)   Quote Red Devil Quote  Post ReplyReply Direct Link To This Post Posted: Oct/21/2017 at 1:59pm
"Normal" is a pretty broad definition.   IIRC, TSM spec is 13 psi @ 600rpm, 37psi above 1600rpm.   75psi max.  

My experience with 2000 rpm +/- cruise is 40-45 psi.   Higher rpms = higher pressure.   Thicker than 10W30 oil or cold temperatures = higher pressure.

At some time the Melling replacement springs seemed to get about 45psi hot and didn't go much higher at higher rpms. Even when shimmed a bit. So I made an adjustable relief with a different spring that got > 65 psi at higher rpms.   That's what I sent Steve to see if it would help him.   And it did. 

I recently tried a newer Melling spring and it got 60psi at higher rpms. So there seems to be some variance in springs over the years, so maybe new ones are fine?

Main point is that the relief is what is primarily controlling high rpm pressure, so make sure it is on your list of things to check. 

Hope this helps,RD

   
Back to Top
SKeown View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Jul/30/2009
Location: Texas
Status: Offline
Points: 3085
Post Options Post Options   Thanks (0) Thanks(0)   Quote SKeown Quote  Post ReplyReply Direct Link To This Post Posted: Oct/21/2017 at 5:04pm

 If the relief spring limits the pressure to 45# then nothing you do will change that. You can tighten up the pump's end play, resort to reduced feed pushrods and even have the lifter bores bushed. You'll still have 45# pressure, that I can guarantee.  

 The OP has shown us a way to determine how much pressure you're engine is capable of. You just need to reverse the bypass plunger and you'll know. So those that stick out there chest and brag about how much oil pressure THERE AMC engine has, it's because the bypass allows that. Take out the spring and shorten it, that will deflate there chest and oil pressure too. 

 A friend had a 304 in a Jeep, the engine was completely worn out including the oil pump cavity and cover, but it still had well over 60#'s of oil pressure. Yes, you can simply shim the spring to increase the pressure, but it's better to have a means to adjust to the desired pressure.

 SKeown
Back to Top
Hurst390 View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Apr/20/2008
Location: secret
Status: Offline
Points: 5752
Post Options Post Options   Thanks (0) Thanks(0)   Quote Hurst390 Quote  Post ReplyReply Direct Link To This Post Posted: Oct/22/2017 at 7:18am
So there we have it..maybe the difference is the springs supplied by mellings...
I just tried to convey that I've never had a problem with pressure..maybe steve just has a weak spring...
SC/Hurst Rambler

11.62 120

100% Street Legal
Back to Top
Boris Badanov View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Dec/14/2013
Location: NH USA
Status: Offline
Points: 4209
Post Options Post Options   Thanks (0) Thanks(0)   Quote Boris Badanov Quote  Post ReplyReply Direct Link To This Post Posted: Oct/22/2017 at 2:10pm
if I thought there was any profit in it I would set up the lathe and make a few hundred sets of -stock to so many tenths(.1) deeper-
caps so people (preferably experienced ones) could play around.

It would be fairly cheap in large numbers. Make em from hex stock.

We have a two spindle multi axis mill turn that is quite fast.
Gremlin Dreams
Back to Top
SKeown View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Jul/30/2009
Location: Texas
Status: Offline
Points: 3085
Post Options Post Options   Thanks (0) Thanks(0)   Quote SKeown Quote  Post ReplyReply Direct Link To This Post Posted: Oct/22/2017 at 4:10pm

 A person could supply everything needed except the pump fitting along with instructions on how to drill and tap the consumers fitting. The complete assembly is well worth $60.00 when you consider how much can be spent chasing ones tail in an attempt to increase oil pressure.

 SKeown
Back to Top
Red Devil View Drop Down
AMC Addicted
AMC Addicted


Joined: Jul/10/2007
Location: Canada
Status: Offline
Points: 1743
Post Options Post Options   Thanks (0) Thanks(0)   Quote Red Devil Quote  Post ReplyReply Direct Link To This Post Posted: Oct/23/2017 at 9:08am
The TA Performance adjuster retails for $19.95. I don't see why an AMC version should cost more than that? If you can tap a hole, buy the TA part and modify the AMC spring retainer to suit. If the Buick thread is the same, it might be a simple bolt-in.

The first adjuster was just a fine thread bolt with the head cut-off and flats ground on it for wrenching and to allow the lock nut to slip over. The seal was a Teflon faucet seal threaded to match the bolt with a steel washer around the seal to prevent extrusion (washer drilled for a snug fit to the od) another steel washer and the locknut. Tapped the stock spring retainer and polished the surface for a good seal.

The second adjuster used a standard set screw and a sealing nut. The retail cost is less than $5.00 for both pieces. Just tapped the stock retainer for the set screw, drilled a shallow coutersink to suit the seal nut and polished the surface so it wouldn't leak.

The spring and seat I scavenged from a scrap logic relief valve. Just happened to have a spring seat and spring that worked ... but the adjuster would work for those who just shim the Melling spring with good results.

The seal nut is manufactured by Bollhoff:
Bollhoff seal nut

Hope this helps,RD
Back to Top
Boris Badanov View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Dec/14/2013
Location: NH USA
Status: Offline
Points: 4209
Post Options Post Options   Thanks (0) Thanks(0)   Quote Boris Badanov Quote  Post ReplyReply Direct Link To This Post Posted: Oct/23/2017 at 11:11am
Small production runs magnify costs exponentially.

Not enough potential volume to make it worth making
any more than one for yourself.

The ones I made for HD's would cost a few hundred each but they
were give-away prototypes, I never made another.
Gremlin Dreams
Back to Top
Red Devil View Drop Down
AMC Addicted
AMC Addicted


Joined: Jul/10/2007
Location: Canada
Status: Offline
Points: 1743
Post Options Post Options   Thanks (0) Thanks(0)   Quote Red Devil Quote  Post ReplyReply Direct Link To This Post Posted: Oct/23/2017 at 11:21am
Bulltear sells the pump relief spring retaining bolt for $13.88. How much extra do you think it would cost to tap a hole when they are already stetup to machine? Add a screw and seal nut and pretty close to the TA price.
Pump relief spring retainer
Back to Top
 Post Reply Post Reply Page  <12345 6>
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.03
Copyright ©2001-2019 Web Wiz Ltd.

This page was generated in 0.156 seconds.
All content of this site Copyright © 2018 TheAMCForum unless otherwise noted, all rights reserved.
PROBLEMS LOGGING IN or REGISTERING:
If you have problems logging in or registering, then please contact a Moderator or