AMC V8 build -- OILING questions

[jeepboy45]

Hey guys.

I've done a good bit of reading about oiling issues of AMC V8's. There are mods to correct this, such as:

drilling additional drain holes in the lifter area
running a line from front to back inside the lifter galley
notching the bottom of the timing cover to allow faster drainback

I've also read opinions stating that as long as the engine isnt going to be run up to the 6K rpm range, none of these mods should even be thought about. If it isnt going to be raced, leave it stock.

Any thoughts about this. Next week my sons and I are going to start putting the 360 back together, and I'd like to address any oiling mods before we get started.

 

[CJ]

One question, are you using a stock engine?

 

[Purple77CJ7]

Hey guys.

I've done a good bit of reading about oiling issues of AMC V8's. There are mods to correct this, such as:

drilling additional drain holes in the lifter area
running a line from front to back inside the lifter galley
notching the bottom of the timing cover to allow faster drainback

I've also read opinions stating that as long as the engine isn't going to be run up to the 6K rpm range, none of these mods should even be thought about. If it isn't going to be raced, leave it stock.

Any thoughts about this. Next week my sons and I are going to start putting the 360 back together, and I'd like to address any oiling mods before we get started.

Everything I have read about says the same as you stated. If your building a race engine then those mods may be necessary, other wise I don't think it's worth the time and expense. I have read too, that some of those mods, if not done right can cause more issues. I would do the oil pump mods, I have done those while apart and think that it's worth the time,ie: mid-plate, check clearance on gears and cover.

 

[coldair]

You can never go wrong with your motor oiling it's self beter. It will last longer make more HP because of less friction.

 

[Incommando]

AMC V8's in stock configuration lasted just as long as everyone else's V8 in that era. Obviously any oiling issues do not effect them in stock-ish applications and at stock-ish rpm/power levels.

Yes, if you have it out and are re-doing it improving the oiling is probably a good thing just like replacing all of the bearings if you spin a rod is better than just replacing the spun one. But to the level of performance you can usually obtain without a major engine tear down the AMC will do just fine as-is.

 

[jeepboy45]

@CJ... yes it is basically stock rebuild

@incommando... getting the block, heads, crank back from machine shop in a week or so. New pistons, oil pump, bearings, etc etc etc...

Not a race rebuild at all. Just a complete, thorough rebuild I hope will last for a LONG time.

@Purple77CJ7...I read a thread from TeamRush about surfacing the oil pump housing and the timing case surface as well to keep from having to use a mid-plate...

Any ideas on doing this and what the clearances inside the pump should be? and how do I measure them?

thanks

 

[CJ]

AMC V8's in stock configuration lasted just as long as everyone else's V8 in that era. Obviously any oiling issues do not effect them in stock-ish applications and at stock-ish rpm/power levels.

Yes, if you have it out and are re-doing it improving the oiling is probably a good thing just like replacing all of the bearings if you spin a rod is better than just replacing the spun one. But to the level of performance you can usually obtain without a major engine tear down the AMC will do just fine as-is.

Truer words have not been spoken...

AMC 8's stock oiling is fine, there are hundreds of thousands of engines running that work,

 

[Purple77CJ7]

To measure side clearance use a feeler gauge between gears and housing. Should be .0025-.005. If it's out of spec. the only way to fix is with a new timing cover. The best way to check clearance for the gear to pump face is with plasti-gauge. The old Chiltons Manual I have shows to use a straight edge across face of gears and feeler gauges. Should be .002-.006. The closer the better with out binding. You use different thickness' of gasket to change. Bulltear has some really thin gaskets for these oil pumps.

 

[Rescue Diver]

Most AMC V8 engine failures are due to the bearings at the rear of the engine from not enough oil pressure making it that far from the pump. If you have the engine out for a rebuild anyway, you might as well spend $3 on some copper tubing and a couple fittings at the hardware store to bypass some of that pressure around the lifters. It's super cheap insurance, and it only takes a half hour to drill and tap a couple holes and plumb it. I did it on the AMC 304 in the Jeep I built in the mid 90's, and it was easy.

As far as the oil return holes, I'll never build any engine without cleaning them up. I've never seen a stock engine block where the castings didn't have extra left over metal from the mold blocking the holes. It only takes a few minutes with a die grinder or dremel to open them up. Just do it before the final clean of the block for assembly. I just opened up the return holes in the block for my stroker build yesterday. I'm running a high volume pump, so I need to make sure the oil gets back to the pan as fast as possible.

You can skip both of these easy steps, and you may never have a failure due to oiling issues, but for so little time and money, why not have a little added insurance???

 

[jeepboy45]

Most AMC V8 engine failures are due to the bearings at the rear of the engine from not enough oil pressure making it that far from the pump. If you have the engine out for a rebuild anyway, you might as well spend $3 on some copper tubing and a couple fittings at the hardware store to bypass some of that pressure around the lifters. It's super cheap insurance, and it only takes a half hour to drill and tap a couple holes and plumb it. I did it on the AMC 304 in the Jeep I built in the mid 90's, and it was easy.QUOTE]


Can you walk me through this....? I might end up doing it...
thanks very much

 

[Rescue Diver]

Most AMC V8 engine failures are due to the bearings at the rear of the engine from not enough oil pressure making it that far from the pump. If you have the engine out for a rebuild anyway, you might as well spend $3 on some copper tubing and a couple fittings at the hardware store to bypass some of that pressure around the lifters. It's super cheap insurance, and it only takes a half hour to drill and tap a couple holes and plumb it. I did it on the AMC 304 in the Jeep I built in the mid 90's, and it was easy.QUOTE]


Can you walk me through this....? I might end up doing it...
thanks very much

Instead of buying the fancy braided hose kit that's commercially available, I just used compression fittings and copper tubing from Ace Hdw. I just found this pic online to give you the general idea. I think this guy may have used a little larger diameter tubing than I did, but I could be wrong. It's been a really long time.

If you decide to do it, make sure you drill the hole between the lifters at an angle so the tube will clear the intake.

 

[suburban99]

Here is some info that I have been saving for a number of years...don't remember where I got it, I did not write it but it all makes sense to me.
I have been saving it for when I rebuild my AMC 304 .

 

[Rescue Diver]

Here is some info that I have been saving for a number of years...don't remember where I got it, I did not write it but it all makes sense to me.
I have been saving it for when I rebuild my AMC 304 .

This is good stuff! I hope anyone building an AMC V8 checks this out!

 

[Rescue Diver]

On the subject of the oil bypass. When I was dropping off the 4.0 block for my stroker, I got to talking to the guy that owns the machine shop about AMC building tips and tricks. As it turns out, they do the bypass on all AMC V8's that they build. He was saying what I already knew. Almost all AMC V8 engine failures are due to the rear bearings not getting enough oil. Instead of the expensive kit or copper tubing from the hardware store, they use a front brake hose and some fittings. I hadn't thought of that one. I didn't get into the details about what vehicle the brake hose is for, or what fittings they use.

 

[jeepboy45]

Here is some info that I have been saving for a number of years...don't remember where I got it, I did not write it but it all makes sense to me.
I have been saving it for when I rebuild my AMC 304 .

I've been debating whether to do any mods or not. As some have wrote, there are thousands of AMC's running around just fine without any mods at all. Good engine building, machine work, and consistent oil changes might be good enough... But I'm leaning towards doing some changes while I still can..

thanks again

 

[Rescue Diver]

I've been debating whether to do any mods or not. As some have wrote, there are thousands of AMC's running around just fine without any mods at all. Good engine building, machine work, and consistent oil changes might be good enough... But I'm leaning towards doing some changes while I still can..

thanks again

It's true that thousands of AMC V8's are running around without problems, but sooner or later all engines fail. The first thing to go in an AMC V8 is almost always the rod bearings at the back of the motor because they're furthest away from the oil pump, and the oil that goes to them has to first go through all of the passenger side lifters.

For just a few dollars in parts, you can protect those bearings, so why not do it while you have it apart?

 

[coldair]

Like I said before anytime you can make any motor oil it's self better you can't go wrong. Think of it this way good insurance on a $1000 investment.