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one bad rambler 
AMC Addicted
Joined: Jan/09/2008
Location: On The Island
Status: Offline
Points: 2007
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 Posted: Dec/21/2016 at 7:24pm |
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Are you sure the pressure relief valve is free in the bore
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 68 AMX 390 4 Speed,68 American,64 American 2 Door Wagon Altered Wheelbase,78 Concord Build 360,727,8.8
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sweatlock
AMC Addicted
Joined: Apr/28/2014
Location: Largo, FL
Status: Offline
Points: 3322
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Posted: Dec/21/2016 at 8:10pm |
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What are you using to measure oil pressure? A known good mechanical oil pressure gauge, the factory electrical sending-unit gauge, a mechanics oil pressure gauge (such as OTC)? The point is, make sure you have an actual problem first...
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jesse
AMC Nut
Joined: Feb/22/2010
Location: Edinburg, Texas
Status: Offline
Points: 299
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Posted: Dec/21/2016 at 8:38pm |
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The spring came out fine but the plunger did not come out easily. Actually i needed to use a magnet to make it come out and it was not easy to pull out. How can i make it move freely in the bore?? Thanks.
Edited by jesse - Dec/21/2016 at 8:52pm
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one bad rambler
AMC Addicted
Joined: Jan/09/2008
Location: On The Island
Status: Offline
Points: 2007
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Posted: Dec/21/2016 at 9:08pm |
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320 wet dry sand paper soaked in wd 40...put a slight cross hatch on the plunger (Keeps it lubed)
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68 AMX 390 4 Speed,68 American,64 American 2 Door Wagon Altered Wheelbase,78 Concord Build 360,727,8.8
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ccowx
AMC Addicted
Joined: Nov/03/2010
Location: Yukon
Status: Offline
Points: 3510
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Posted: Dec/21/2016 at 9:16pm |
For pre oiling, it would seem to me that the bearings, top end and other areas of the engine have a decent coat of oil, if it has been run since rebuild. Rather than fill the oil pump cavity with vaseline, would you not just be able to remove the coil wire and crank the engine until the idiot light goes out? Once you have oil pressure throughout the system it should be just like any other startup. I do much the same with my own car when I change the oil filter. Putting some in the filter(which I do) does not seem to give me instant oil pressure at initial fire up, so I like to make sure it is all full when the engine actually starts up.
I am not worried about the vaseline per se, but I like to err on the side of less contaminants, additives, etc in the oil wherever possible. Just a matter of principal!
Chris
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1970390amx
AMC Addicted
Joined: Jul/11/2008
Location: colorado
Status: Offline
Points: 3314
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Posted: Dec/21/2016 at 11:33pm |
Cranking a engine without oil pressure is not good on the bearings. I would prefer a few seconds of running to build oil pressure and then its oiling the piston skirts and can surfaces from splash. I only use the vaseline in a new pump to make sure it primes as fast as it can, not all engines can the oil pump be driven without running the engine.
As to the original post.. an engine oiling system is one big leak. Oil leaks past the bearings it leaks to lube the lifters then the cam lobes, it leaks all over the valve train. The first leak I would worry about is internal to the pump. After installing the new gears you need to make sure end play is in the correct range. To thick of a gasket can cause problems. Second is the pressure bypass system. If the valve is difficult to remove when cold what happens when the aluminum housing expands when hot? If that happens and the valve is stuck in a open position and the oil thins as it gets hot you lose oil pressure. If you have to much bearing clearance it only aggravates the problem. It sounds like you put new standard bearings on a used standard crank, I would bet you have .001 or .002 more clearance than you should. It might be close to spec but if you have other problems it will cause oil problems. Did you replace the cam bearings? All of this is just one more leak just a little bigger than you might want. Just my two cents worth
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1970 390 4speed Bittersweet shadow mask AMX
1970 Amx missing most everything, or in a box
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ccowx
AMC Addicted
Joined: Nov/03/2010
Location: Yukon
Status: Offline
Points: 3510
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Posted: Dec/22/2016 at 12:07am |
Just exploring this for the sake of learning, not argument. It would seem to me that cranking the engine without oil pressure is going to be better than running it without oil pressure? Even at idle there would be the push of combustion on the individual pistons etc. Is there something I am missing here? Obviously ideal is the remove the dissy and prime it and then run it immediately, but no one does that just to change the oil.
Thanks!
Chris
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Hurst390
AMC Addicted
Joined: Apr/20/2008
Location: secret
Status: Offline
Points: 5822
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Posted: Dec/22/2016 at 5:54am |
A small amount of Vaseline is ok but people always say "Pack" the cavity..What happens to the stuff till it melts? It stacks up in your oil filter reducing flow.. No need for it in my world..I fill the filter with oil and turn the pump backwards till the gears get oil then turn the pump clockwise to prime the engine. I would prime the engine anytime over just using Vaseline... And to add if you have a new bulltear cover you shouldn't have to be messing with oil pump gears anyway..
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SC/Hurst Rambler
11.62 120
100% Street Legal
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Rebel Machine
AMC Addicted
Joined: Jul/03/2007
Location: Western Il
Status: Offline
Points: 5121
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Posted: Dec/22/2016 at 6:54am |
 jesse wrote:
Main and Rod bearings are standard size since thats what came off during the rebuild and crank and rods have not been machined. |
Take it apart and measure the the clearances. Clearance on rod bearings and mains 1 through 4 need to be 0.001"-0.002" and main 5 need to be 0.002" - 0.003". If bearing clearance is excessive you'll have a low oil pressure problem and you'll see the cam bearings being stripped of their babbit like this:  -Steve-
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farna
Supporter of TheAMCForum
Moderator Lost Dealership Project
Joined: Jul/08/2007
Location: South Carolina
Status: Offline
Points: 19692
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Posted: Dec/22/2016 at 7:31am |
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End play on the gears in the oil pump is critical. Looks like you may not have enough, which could cause the gears to bind a bit, increasing the load on the distributor drive gear (which also drives the oil pump) and possibly reducing pressure. Take the cover off, use some Plastigage, put it back on and torque down to spec, then pull it back off and read the Plastigage. Adjust gasket thickness to get correct end play. End play is more important than clearance in the gear cavity between gears and walls. Oil going through the gears gets pushed through under pressure, oil going around the end is not pressurized.
I'm with the others -- what gauge are you using and where is it connected? The factory electric gauge can be wrong... poor connection somewhere, bad sending unit. You need a known good mechanical gauge. You can just connect under the hood to check cold, run it a bit then pull over and check hot idle. You should have at least 15 psi at hot idle (engine at full operating temp).
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Frank Swygert
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Oil Pump Gear Kit Installation