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Discussion Starter · #1 ·
/wwwthreads_images/icons/tongue.gif My moonguy/wwwthreads_images/icons/wink.gif/wwwthreads_images/icons/smile.gif/wwwthreads_images/icons/wink.gifcrew has taken the water pump off the 304 for inspection, and I was taking a good look at it today. What I noticed was that the by-pass hose that comes from the thermostat housing is real generous, and feeds directly into the suction cavity behind the water pump impeller. We aren't experiencing any overheating problems at present, but we ARE planning to add Air Conditioning for summer driving. Looking at the by-pass setup, it occurred to me that this very large hose may be recirculating too much water back to the block when the engine is up to operating temperature and beyond, taking away some much needed circulation through the radiator. I'm going to have my chief machinist moonguy/wwwthreads_images/icons/wink.gif make a stainless bushing to fit into the hose just past the water pump nipple, held in place with an external hose clamp, and with a bore not bigger than about 7/16". By restricting the flow, I can force more water out of the back end of the engine and through the always-open heater circuit during warm-up, plus have more net flow through the radiator when I really need the cooling, instead of having a lot of water re-circulating locally right there in front. Think about this....SB Chevys don't even HAVE a by-pass except for the always-open heater loop.(Which is ONE reason why they MUST have a hole drilled through the thermostat)/wwwthreads_images/icons/smile.gif So, why would the AMC V8 have such a big by-pass? Well, it might be as simple as the water pump casting. Maybe when the designer took the drawings to the factory guys, they crabbed about the small aluminum nipples sticking out of the casting, and complained that core shift would cause too many scrappers. So....the engineer might have given in and went back to the drawing board and made them HUGE./wwwthreads_images/icons/frown.gif That's what happens in production situations. The machine is a compromise between what the engineer wants, and what the factory guys, in their infinite crabbiness, are willing to give him./wwwthreads_images/icons/crazy.gif

CJDave
I never believe any statistics unless my moonguys /wwwthreads_images/icons/crazy.gif/wwwthreads_images/icons/wink.gif made 'em up themselves.
 

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Re: Overheating 304/360/401???

Dave, What did you ever do for the fan and clutch? Did you do that Chevy 19" or 18" fan? Thanks..Please keep us up on your moonguy's research..Thanks

Ricky...seeya...
1979 CJ-7 401 T18
 

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Re: Overheating 304/360/401???

I was looking at that very same thing last night while playing with the oiling system... Odd you would mention it today...
If you take a good look at the way the heads are made, and the way the water flow is routed, I kind of wonder if that wasn't intended to 'burp' the system. You know, help pass steam when the system gets hot...
I had the same idea you had about the restrictor. I think I'm going to wait till there are a few more miles on it for a baseline before I do it though, so I have a realistic database to go from.

I had to clear my cache in my email program (getting way to big), and I pushed the wrong button and lost all of our emails.
I can't remember if you wanted pictures of my external oiling line or not.... Let me know if you do.

I almost forgot to mention... I drilled a hole into the front oil gallery where the cam gear thrust (friction) face is, so it's oiled, and I drilled a hole in the front gallery plug behind the cam gear, and used your mig tip idea to spray the chain it's self...
Now, with the new idea you gave me for the mig tip/ distributor gear oiler, I shouldn't have any dry spots on the front end.

I saw something last night that might be of service in a little while, once I figure it out.
The cam drive gear has slots or holes in it.
(We are using an Edelbrock true roller set, so about half of the gear is slotted)
Those slots align with the lifter gallery plugs.
If a restricted mig tip was threaded into that even bank gallery plug....
and aimed at the distributor gear and fuel pump eccentric...
(MIG welder tip is both cheap, easy to aim, and a precise orifice and restriction)
Half the time the oil stream would spray on the back of the cam gear and lube the otherwise dry timing chain, and the other half of the time the oil stream would lube the attachments on the front of the cam.
There is plenty of room behind the cam gear to clear it, and I'm still looking for a reason why not...
(Pretty much making all the external stuff we've been doing obsolete....)
It wouldn't be susceptible to damage like the external oil line is.

What do you think? Will it work?...
If it doesn't, all I'm out is a mig tip ($1.12), and a socket head brass pipe plug ($1.95)
(Hobart mig tips have really nice little flats machined into them at the tip to make it easier to remove them... My Miller tips don't, and the Lincoln tips are a smaller thread and don't have the flats)
---------------------------------

Use the even bank plug, it gets direct oiling from the pump.
Use a socket head (allen wrench) plug for the extra clearance...
Run the plug in, mark it for drill location and angle...
Take it out, drill and thread it...
Run it back in, and screw in the mig tip with some red thread locker...
Presto, chango, you're done, and the front end has oil for a change...
(Not the way AMC intended it, but better than the factory idea of changing that stuff every 45 to 50,000 miles like it says in the service manual...)

(We better stop talking about new ideas like this in an open forum, or they will show up on parts mike's page or as a kit from some vendor for $300...)

Let me know what you think....
Later all, Aaron.

If Chris Columbus "Discovered" America (with 25 million already here), Can I Go "Discover" Florida?
 

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Re: Overheating 304/360/401???

Last time CJ Dave an I talked about it, we were both going to try 0.025".
I am going to pressure test a few different sizes with engine oil, probably warm 10W40 to see what kind of flow and volume we would get at about 30 psi and again at 50 psi.
If you can't hold 30 at idle, it's time for a rebuild or new oil pump.

I'll post what I turn up.
CJ Dave had a GREAT idea with the mig tip, and I'm going to run with it...
Looks like some others are interested also...

Say thanks to CJ Dave, he's the one with the initial idea...

If Chris Columbus "Discovered" America (with 25 million already here), Can I Go "Discover" Florida?
 
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Re: Overheating 304/360/401???

While you guys are on the topic of oiling, I am wondering if you are running an oil line inside the lifter valley from the pump to the rear to provide oiling in the back of the engine. I have also seen AMC builders drill and chamfer a 1/8" hole in the bottom of the lifter valley just outside the lifter bores to provide additional oil to the cam bearings. I'm planning on building a 360 some time this summer and am trying to learn as much about these AMC V8's as possible. Never done anything V8 that wasn't GM!
 

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Discussion Starter · #7 ·
Re: Overheating 304/360/401???

/wwwthreads_images/icons/smile.gif Hmmmm....the ONLY rub I can see with the EVEN SIDE oiler tap is that it is the side that is oiling everything in the whole engine but the ODD SIDE lifters. Can you use the ODD SIDE instead? Somehow.. Also, SNOWTOW mentioned the rear oiling enhancement. I am trying to make that obsolete also by doing a crossover BEHIND THE FLYWHEEL. Every other V8 ever built has a crossover except this one. And the rear crank oiling just isn't very good without some enhancement./wwwthreads_images/icons/wink.gif No, TeamRush...I'm OK about the oiling text. As for the heads, if it were a steam problem, wouldn't the guy have gone to the radiator? Like with a cast thermostat by-pass, small, but there./wwwthreads_images/icons/crazy.gif Boy...some good stuff on here today, and I gotta leave...DRAT!/wwwthreads_images/icons/frown.gif

CJDave
I never believe any statistics unless my moonguys /wwwthreads_images/icons/crazy.gif/wwwthreads_images/icons/wink.gif made 'em up themselves.
 

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Re: Overheating 304/360/401???

I thought the Even side because it's continuous feed from the oil pump, and it's got the straightest shot at the distributor gear.
It really shouldn't matter which side.
The odd side gets oil from the same supply in the front of the block if I remember correctly, so that shouldn't matter. lost volume is lost volume to the back...
To bad they didn't cast in a cross over in the back like they did in the front...
That would have cost an extra $0.13 by the time the extra cast iron and machine work was done...
(friggin' bean counters...)

The 'burp' was just a guess. I don't know for sure...
I cut apart several heads when we were doing machine work, and I'm convinced there is a considerable amount of steam produced in several hot spots in the heads.
I don't have a clue...
I thought about a restriction down to about 3/8". That should allow a fair amount of flow with out causing problems.
I might even try 1/4"....

I was going to do some testing on the oil flow we talked about, but it cold and sleet/ raining here today, and my back has been giving me fits sense the cold weather came back...
I was enjoying those record 70 and 75 degree days there....
All my trees and flowers budded out, I hope it doesn't freeze again, but I have a feeling it's going to...

Later guys, I have a heating pad and girlfriend calling my name...
Aaron.

If Chris Columbus "Discovered" America (with 25 million already here), Can I Go "Discover" Florida?
 
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