Hot Rods 318 Mopar HEI Brakedown on way to Frog Follies

Electronics are mostly better....but they weren't around when the really neat cars were built.

And it's a blast to run that old antiquated crap in an old hot rod, and get to your destination. You know you've accomplished something.

 

What seems to be missed often on this thread is that the GM HEI failed. It was not the 318's problem someone swapped in the failed GM ignition stuff.

The HEI module is at the bottom of the distributer and will be the 1st thing effected by the oil if that indeed was the cause of the failure. Most HEI failures (after the burned through rotor) was the wires that connect to the module failing and killing the module. The addition of motor oil also would not help the heat sink under the module much.

You need to pull the HEI and check the wires to the module and the module itself to be sure that stuff is good. While your there, find out why and how the oil is getting into the distributer, and see if you can correct that problem.

Points and condensers failed every 10,000 miles, and caused the plugs to fail along with them. That was why the government forced electronic ignition onto the auto companies. The auto companies were very happy to keep selling you sparkplugs, points, and condensers. Electronic ignitions would have never come along if people would have kept their cars tuned. Since the people didn't take care of their stuff, the government stepped in to force the auto companies to find ways the state of tune didn't change much over 50,000 miles, and points & condensers didn't last that long. People still don't want to change the sparkplugs until they misfire.

 

Checked all the externals yesterday (PVC, breather, wiring, oil pressure sender base, etc.), as per suggestions on this thread. Will pick up a new breather and PVC today even thou they appear OK. Cleaned the back base of the 318 with carb cleaner. No oil on the firewall so it doesn't seem to be leaking/spraying at the back by the HEI. Will make sure all oil is gone from the HEI today and then run the engine and see if I can find any sign of excessive crankcase pressure and/or external source of oil before I move on to the pulling the HEI.

My hope is we can stay on topic and not let this thread evolve into a points vs HEI conversation. Again, thanks for all the responses.

 

What’s sad is owners today who are so use to modern vehicles needing so little maintenance who buy cars of their past because of what are perceived as great memories. How often does anyone raise the hoods of the OT cars? In out youth is was done everytime you bought gas; today it may never be opened between oil changes if you have a tag on your windshield showing the mileage when it’s do.
The owners/buyers today might not have really been “car” guys anyway but now have the $$$ to get what they want. I see this as LS’s replace all the SBC’s and leaking flatheads.
There are good electronics today that don’t need the HEI look….use them instead.

 

Jim GM offered a pointless ignition on 1963 Pontic 389 and 421 engines and offered in 64 on Corvettes option K66

 

Aftermarket CD ignition amplifiers were available in the early 60s, too. Most guys didn't want to have anything to do with them.

Sure is curious about the oil in the distributor.

 

Not to change the topic but this was one of the reasons I bought the 57 Chevy a while back. I was watching other potential buyers and was getting a sick feeling from either lack of know how or where they wanted to transform it.

 

So thinking about the oil problem..............
I guess the only way the oil could have gotten into the upper distributor is being pushed there by crankcase pressure. While you have the distributor removed, would it be possible to spray some oil into the bottom of the housing while holding it inverted ? This might give you some idea of whether it has too much clearance in the upper bushing. Also, are you using a synthetic oil that might work its way thru tighter clearances? Last idea is hooking up a guage that would show you how much crankcase pressure you have while driving the vehicle.
It is possible that the oil had been gradually building up and just finally became enough to be an issue. Guess you could always put a drain hole in it.........

 

I like the drain hole idea

 

Can you compare the bottom of the original distributor to the new one? Does it have an oil hole just above the gear, or any other holes that the stock one doesn't? If not caused by crank case pressure, something is different about the distributor, and the high oil pressure is getting into the distributor some how. Also it looks like there is a plug right in front of the distributor driven gear that you can see if you look down the hole. I assume it's for an oil galley, make sure it's in there.

 

And condenser. That's where a lot of new stuff misses the mark. Even NOS are often bad after setting on the shelf for who knows how long. A good reason to add a multimeter with a capacitor test function to the tool box. Those were rare and expensive at one time but have come down in price and improved in availability. Needed for electric motor and air conditioning work too.

 

Unfortunately a multimeter usually only tests the capacitance, and it does it at a very low voltage. This means leakage (self discharge) and other properties at the actual working voltage with peaks of many hundred volts can not be tested - so you still don't get a fool proof test, but it's at least a partial test and I suppose that can be better than nothing.

I would expect the capacitor tester on an old distributor tester or similar automotive test equipment to be more accurate. The guys who designed them to test automotive condensers had a good idea what they were doing.

 

30,000 miles? Is that all? Actually, its pretty amazing. I'm guessing that you probably didn't throw those points in the Chevy, then forget about them for 30K miles, did you? You probably checked them, flied the contact surface, and maybe even lubed the rubbing block during those miles.

I was a tune up guy at one of the largest auto service centers in our town in the early 70s. I have changed a lot of sets of points through those years (I could set the point gap by eye and have the dwell in spec nearly every time, that comes from changing a lot of sets of points).

We had one guy that came in with a 64 Chrysler that had a misfire (would have been around 1976, we all knew the guy and the car). The car had 78,000 miles on it (he bought it new), the guy could not recalled ever having had it tuned up, so I did one. There was no curved electrode left on any of the plugs. The point contacts were welded together and the arm on the points had broken and it was running by using the broken arm as the contact point. One super hero set of points in 100,000 sets doesn't mean much.

In those days, 10,000 miles on a set of points put that set near the super hero status. Most had worn rubbing blocks, mountain size build ups on one side and grand canyon craters on the other side of the contact surfaces, and closing springs that barely functioned, in less then 6 to 8 months of daily use. Probably less then 25% of the point sets we changed out during annual tune ups would have made it another 6 months, the other 75% were already toast.

Like most of the rules on the race tracks, the reasons why mechanical point systems are no longer the main ignition systems have been learned by experience.

The OEM Mopar electronic ignition system on my 72 Plymouth (it was an option when the car was new) lasted over 140,000 miles (that I personally put on the car) before it was moved to the next vehicle where it went at least another 20,000 miles.

That Plymouth was not the only Mopar Electronic Ignition I never had any issues with, it was one of probably more then a 100 of them I had in my possession over the years. I have never personally had a Mopar Electronic Ignition fail for me (I did carry an extra resistor with me, never has to change one). Can't say that for points (I carried an extra set of points in the glove box). There were a few of the Hall effect ignitions that had the pickup fail, but being a trained mechanic in their function, that was easy to fix (didn't happen enough to warrant caring an extra).

I really have nothing against points except the frequency in which they need to be serviced so they continue to function. It didn't work with the drivers of the 70s, and there is less chance of it working these days. For the people that do not know how to install and set the dwell on a set points themselves, finding a guy that calls himself a mechanic these days that is qualified to install and set the dwell on a set of points is very difficult. To expect newbies to be able to do so probably isn't helping the hobby much.

 

Picked up new breathers and PCV yesterday afternoon. I don't think they are the problem, but just narrow it down I replaced them. Also blotted up the oil in the HEI. There was about a 1/8 cup in it. More than in the picture. Enough to cover the contacts on the module.

Putting it back together in the morning and, if it starts, will let it run for awhile and then check the HEI to see of more oil is there. As ekimneirbo suggested I also think it is coming up the shaft because of excess crankcase pressure. Will know more after it runs for awhile. Only problem with drilling a hole in the bottom of the HEI is figuring out where to drain it to. Will let you all know what the results are.

 

Got it all back together, started it in the shop and it ran fine. Will let it idle for a while this morning, check the HEI for oil and then try driving it around.

 

Seems to have a flat washer (felt?) seal under the shaft at the top of the housing, and obviously the tight tolerance between the shaft and the housing to control oil. I didn't see an O-ring at any point in the OE design. The gear is on the intermediate shaft, not the base of the dist. so there shouldn't be much 'windage' climbing the shaft inside, just a lot of splash from the valvetrain. The cap shouldn't allow much ventilation, so the oil should not be migrating inside. You may have fixed the ignition loss by cleaning the dist, but the root cause of the oil going in should be found and fixed. Maybe call the company and ask if others have experienced this and how they feel about various methods for limiting oil migration inside. Maybe a seal or O-ring at the base of the housing or a slinger on the shaft.

 

I test condensers all the time, and unfortunately the units built into most Sun machines have failed capacitors in them so the readings they give is incorrect. I have a commercial version of an automotive capacitor tester that gets calibrated once in a while and serves the purpose very well. 50 year old condensers were paper/foil and do not hold up to the test of time.

Yes, this is 100% a crankcase pressurization issue, but be wary drilling holes in the HEI casting - you have electrical and exhaust that will get covered in oil which is more than dangerous. Mitigate the pressure. Give it somewhere LARGER to go. Let the air cleaner suck on a 3/8" ID hose. Think big.

 

I'd change your valve cover breather to the type with the nipple that allows you to connect a hose from the valve cover to the air filter.

 

Why not put a pressure gauge on one of the breathers and run the engine and see if it's a case of too much crank case pressure? Right now everyone is just guessing as to the cause. Did you look at the bottom of the distributor or checked what I mentioned in post 70?

 

Yes, driver side lifter galley. If the plug is not there then you will have little or no oil pressure...although that might fix the problem at hand...

 

I also have very good life from a set of points. My 8CM flathead in the '41 Merc has a bit over 20,000 miles on the points and they look great. A dab of grease a couple times on the rubbing block is all I've done. Condenser is a modern capacitor in a vintage brass can by Tubman.

I agree with the crankcase pressure diagnosis. Make that crankcase free breathing and I'll bet the problem is cured. I also think the aftermarket "HEI for everything" is an ugly setup....but that's just me.

Terry

 

I haven't pulled the HEI "yet". Ran the engine in the shop yeaterday after replacing all the breathers. Started right up and then after 15 minutes took it out for a drive. No problems. Oil pressure while idling in the shop was 75 lbs. When in gear driving it dropped to just over 50. So, 73RR, I have plenty of oil pressure which would indicate the plug is in there, but I will check when I pull the HEI.

I will pull the cap this morning and see if any oil is in the base of the HEI from yesterday's run. Possible that changing the breathers may have solved the problem but unlikely. Next step is to pull the HEI and see if oil is somehow coming up the shaft.

 

I'd love to know what your oil pressure is, with engine warmed up to operating temp, sitting in gear at a light ... as it stands right now, your "I have plenty of oil pressure" comment seems to me to be somewhat of a massive understatement. This is a street driven 318 isn't it?

Why is the oil pressure so high?

 

We have no idea how accurate the oil pressure gauge is, if it is a mechanical gauge, or an electric gauge, or the condition of the oil pressure sender for an electric gauge might be in. A faulty gauge or sender could max out the gauge, or show 5 psi. I have no doubt he sees the oil pressure the gauge is showing, there may be questions about how accurately that gauge is showing the real oil pressure.

That said, I have seen high oil pressure on a lot of small block Mopars (it usually drops after a year or so of use). Tight cam to cam bearing clearance will boost the oil pressure in a small block Mopar fast. Most people buy a cam kit, and shove the cam into the existing bearings without any idea how much clearance is there. Warn oil in a warm motor, going down the highway at 3,000 RPM, that shows 50-60 PSI oil pressure is not unusual.

75 PSI in the shop, idling with a cold motor, is pretty high. Wonder what that oil pressure looks like going down the highway at 3,000 RPM cold? 75 PSI is pushing the limits of many oil filters.

 

I don't know what the pressure ended up being but years ago a friend "shimmed the spring" on his 340 oil pump and blew up the oil filter

 

He says he has 50# oil pressure warmed up, in gear and driving. No problem. High oil pressure isn't going to force oil up a distributor shaft in a sb Mopar anyway.

 

True on a Mopar distributer, except the distributer in question is not a Mopar distributer, its a HEI look a like conversion of foreign origin.

 

I have seen some replacement dist shafts that have a spiral groove cut in them to push oil down . If a manufacturer decided to copy that design on a dist shaft that turns the other way it would be pushing it up. I wonder?