SLANTY BLUES

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RAT ROD AL

RAT ROD AL

MOPAR ARCHAEOLOGIST - one parts hoard at a time!
FABO Gold Member
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Location
Robbinsville, North Carolina
No It's not a song. Been rehabbing my old A100 . Rebuilt the engine a few months back, running great, swapped in a 904 along with the new engine. 904 was a used one I had laying around in the garage for a few years. Known to be good. Fixed up the inside , just put some high back recliners in front to make it more comftiy for road tripping.Last week I finished up a front disc conversion, One day before my planned road trip up to Smokey Mountains. ( I live in S/W Florida. Get the van all loaded up with all the crap (and more) we needed and hooked the trailer and bike on back and off we go.

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headed North on 75 . 4 hours into the trip it started getting hot, hit a rest stop and put in a gallon and a half of water. looked like it came out the cap.got back on the road and in about 10 miles it started getting hot again. Whistling it's tune, gauge was reading 210 ish. Made it to the Don Garlits race museum. Checked it out there and it was done. Steaming and spitting coolant out the tail pipe. Unloaded the bike drove it back home, Left the van and trailer in thr parking lot at Dons. Had to drive all the way back up there the next morning In our truck . Rented a tow dolly, loaded the van and headed back home, like a train. Now My 2014 Ram pulling all this crap down the highway at 70- 75 got better gas mileage than the van, had A/C AND We could hear the radio. This just might be the way to go next time !! LOL

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Nice van.
Also brings back some memories because it looked just about like that at my house.
I had the same van all white and without any side windows, 2 dresser bikes and a boat in my front yard.
 
So to get to the point . I got it home . Today I pulled the head to find a blown head gasket between # 5 & 6. Pulled the plugs out first and all were spitting coolant. #1 piston looks crispy brown , maybe the only one not wet or running lean. I had the head milled .020 and the block also milled .020 to raise comp. Used a felpro head gasket ( stocker). Is that type gasket good enough with the milling done or is there better ones ? Maybe a steel shim type. And also It didn't make a lot of noise while it was running , but after I shut it off and the cylinder fill with coolant it banged and kicked back trying to start restart it. It did restart and spit all the coolant out the exhaust. Is it possible it screwed the rod bearings up from hydraulicing upon starting it up? Any input on this issue will be appreciated. Thanks Guys. Of all the repairs to the old van the engine was the least of my worries.
 
Man that really sucks. I hate that your trip got diverted. I hope you can get it figured out. I love the smokey mountains. I am only about 4 hours maybe less from them and still dont go as often as I'd like. The way you where going you probably would go right by me!!
 
Since the head is off, check all the deck heights and compare them to each other. As well ,check for any not sitting square and level.

I hate to think this way, but suppose the hydraulic lock pushed the gasket out. Suppose the water didn't get in there from the moved gasket, but rather from a crack in the head or water jacket?
Just suppose.
So; I suppose a pressure test is in order for both the head and the block
 
Man that sucks. Engine work in a van even sucks more. I think after a few overheatings I'd be looking at the block too. Taking off the amount you said wouldn't have upped the compression so much you would need a different head gasket. Look at the radiator, water pump you know the drill. The complete cooling system. But it is hot in Florida so a good cooling system is a must. Good luck my friend.
 
After reading post #3, I need to correct the Milled #s. I had each milled .040 for a total of .080 . I did a compression check before I took it apart. 1- 4 ranged from 215 down to 175 And 5 was 50 , 6 was about 85. On a fresh rebuild I'd hope for closer readings than the span of the 1 - 4. But is is what it is. No sign of coolant in the oil pan by looking at the dip stick today. I will have to drain the pan and check closer for water , but if the oil looks good, wouldn't that rule out a crack in the block and head? I ran it quite a ways before it overheated the second time.
 
dartfreak75 said:
Man that really sucks. I hate that your trip got diverted. I hope you can get it figured out. I love the smokey mountains. I am only about 4 hours maybe less from them and still dont go as often as I'd like. The way you where going you probably would go right by me!!
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My planned route was N75 to Macon GA then take 441 into Maggie Valley N C. I believe you are further North.
 
215 and 175 are both too high(see edit,below)for pump gas. My guess it there was still liquid in those holes at the time of the test.
The low ones 50 and 85 were probably low due to lack of oil on the cylinder walls.

Edit; Too high because the liquid takes up space and artificially increases the gauge reading. So in reality, this compression test is probably meaningless.
 
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On a side note: Did anyone bother you towing in tandem like that?
Up here in the North East, Towing tandems even on a small scale like what you did would get you ticketed, shut down and two tow trucks.
I agree- Van looks good.... SMALL BLOCK it!
 
AJ/FormS said:
215 and 175 are both too high for pump gas. My guess it there was still liquid in those holes at the time of the test.
The low ones 50 and 85 were probably low due to lack of oil on the cylinder walls.
Click to expand...

The low ones , 5 & 6 had the bad part in the head gasket. **** I didn't want to run this thing on race gas. LOL I do have other heads . If unmilled that would make only the block -.040. Just spent a small fortune on this head. New everything. Thanks AJ
 
RAT ROD AL said:
My planned route was N75 to Macon GA then take 441 into Maggie Valley N C. I believe you are further North.
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Yea I am further north! You would have to take 77 in then 81 to come pass me!! I cant remember the name of the interstate but 77 turns into something else goes pretty much straight thru Georgia.
 
Here's my thinking;
Water in the cylinder will flash to steam during the combustion event, then condense back to water in the exhaust system. During the time the water is changing phases it sucks a tremendous amount of heat out of the combustion event. You should have noticed this as a huge powerloss, having to drive pretty deep into the carb. And of course the large throttle opening would suck gas.
As the water level in the rad gets used up and goes out the tailpipe, the engine overheats, you see it on the gauge and pull over, and shut it off. Now the system pressure rises and blows water into the chamber, or chambers. You fill up the rad and hit the starter with accompanying hydro lock. But you get it started and drive off, only to have this repeat.
My thinking is that the hydrolock couldda pushed the gasket out, and came after the initial overheat. So in this scenario, if it is accurate, you gotta go looking for where the water was entering the chamber.
Yes it could still be the headgasket.... but then the water shouldda sprayed out all over the dog-house and the outside of the engine.
I know the pressure tests cost money, but if you assume it's just the headgasket and put it all back together,under this assumption, and it does it again, which costs more?
At least;
Lay the headgasket back onto the engine,and onto the head; and see if the water is able to sneak around the fire ring, where it is pushed out.
Oh I missed that the low ones were the blown ones, I assumed they were among the 1thru 4. Therefore if 1 thru 4 were as high as you say, then yes you are gonna need racegas, or an anti-detonant-injection, when running at or near WOT, but probably not at cruising, because your effective compression ratio may still be in the range of pumpgas. Detonation is your measuring stick, and is to be avoided at all cost. Detonation may have driven the gasket out. So you will have to go looking for the evidence
So most of post 10 may be meaningless, as the first 60% of this one.

On a fresh rebuild the pressures should vary hardly at all. Because yours vary so much, this could be another sign of detonation, look hard
 
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Syleng1 said:
On a side note: Did anyone bother you towing in tandem like that?
Up here in the North East, Towing tandems even on a small scale like what you did would get you ticketed, shut down and two tow trucks.
I agree- Van looks good.... SMALL BLOCK it!
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NO , I didn't get stopped. I would have said I have a C D L for pulling doubles. LOL. I have seen people pulling stuff like a 5th wheel trailer with a boat hooked on back of that down here in Fl . which gave me the idea. Didn't want to have to make 2 trips. Don't know if it's legal though. Maybe I just got lucky.
 
AJ/FormS said:
Here's my thinking;
Water in the cylinder will flash to steam during the combustion event, then condense back to water in the exhaust system. During the time the water is changing phases it sucks a tremendous amount of heat out of the combustion event. You should have noticed this as a huge powerloss, having to drive pretty deep into the carb. And of course the large throttle opening would suck gas.
As the water level in the rad gets used up and goes out the tailpipe, the engine overheats, you see it on the gauge and pull over, and shut it off. Now the system pressure rises and blows water into the chamber, or chambers. You fill up the rad and hit the starter with accompanying hydro lock. But you get it started and drive off, only to have this repeat.
My thinking is that the hydrolock couldda pushed the gasket out, and came after the initial overheat. So in this scenario, if it is accurate, you gotta go looking for where the water was entering the chamber.
Yes it could still be the headgasket.... but then the water shouldda sprayed out all over the dog-house and the outside of the engine.
I know the pressure tests cost money, but if you assume it's just the headgasket and put it all back together,under this assumption, and it does it again, which costs more?
At least;
Lay the headgasket back onto the engine,and onto the head; and see if the water is able to sneak around the fire ring, where it is pushed out.
Oh I missed that the low ones were the blown ones, I assumed they were among the 1thru 4. Therefore if 1 thru 4 were as high as you say, then yes you are gonna need racegas, or an anti-detonant-injection, when running at or near WOT, but probably not at cruising, because your effective compression ratio may still be in the range of pumpgas. Detonation is your measuring stick, and is to be avoided at all cost. Detonation may have driven the gasket out. So you will have to go looking for the evidence
So most of post 10 may be meaningless
Click to expand...

The detonation theory is what I was expecting to see when I popped the head off. The van is really noisy from wind noise, on top of me being hard of hearing( LOL). But as we were driving I was listening to the engine. My wife said she could here some clicking (?) coming from the engine, but couldn't describe it , so I blew it off. All before it over heated the first time. The head gasket on # 6 looks like a burned spot in the sealing ring towards the back side of the cyl, then pushed towards # 5. #1 piston looks burnt brown (lean). ? Maybe #6 was the same before the gasket blew. Any thoughts?
 
Detonation/ preignition shows up on the sparkplugs as melted electrodes/ and or silver flecks on the porcelain. And I have seen holes hammered thru the tops of the pistons right in the center, and melted top ring lands as if cut by a blow-torch.

Brown tops is perhaps lean; if they smell like Dobeman DooDoo then lean for sure. This is probablyOk for cruising with a good cooling system, as long as the power circuits are richer.
Do you recall what you lashed the valves to?
Mine likes .013/.023, lashed at about 72*F. IIRC the spec is .010/.020/HOT. But by the time you get the cover off and have checked the last one....... the engine ain't hot nomo. Plus the valve stems beat up the rocker arms pretty bad over time, and the pads end up with ruts in them. And then you cannot use a regular feeler any more. I cut my feelers to fit in the grooves.
 
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AJ/FormS said:
Detonation/ preignition shows up on the sparkplugs as melted electrodes/ and or silver flecks on the porcelain. And I have seen holes hammered thru the tops of the pistons right in the center, and melted top ring lands as if cut by a blow-torch.

Brown tops is perhaps lean; if they smell like Dobeman DooDoo then lean for sure. This is probablyOk for cruising with a good cooling system, as long as the power circuits are richer.
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I think I saw some flecks up in the combustion chamber of the head. I had some E3 plugs in it. I didn't clean them yet.I'll check em. I had it timed @ 12 * initial timing. And running a holley 1920 with a 56 jet, would uping the jet some help the power circuit? Thanks AJ, I really appreciate your time and help.
 
RAT ROD AL said:
I think I saw some flecks up in the combustion chamber of the head. I had some E3 plugs in it. I didn't clean them yet.I'll check em. I had it timed @ 12 * initial timing. And running a holley 1920 with a 56 jet, would uping the jet some help the power circuit? Thanks AJ, I really appreciate your time and help.
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We are all here for you.
If you are needing to drive that deep into the carb then yes a bigger MJ will richen it up.
Detonation does not usually occur at steady state cruising. If conditions are right, it will usually manifest when running deeper into the carb.and at higher load settings, as in acceleration.
Pre-ignition however, can occur at any throttle setting, and usually leads straight into detonation. Pre-ignition is when something in the chamber lights the fire before the sparkplug does. When the spark plug then fires, the two flame fronts collide in the chamber, the pressure sky rockets, and you hear it as a rattle. That pressure spike usually breaks stuff, like the pistons if allowed to continue, and can smash sparkplugs. I guess it could also blow the fire rings out
 
AJ/FormS said:
We are all here for you.
If you are needing to drive that deep into the carb then yes a bigger MJ will richen it up.
Detonation does not usually occur at steady state cruising. If conditions are right, it will usually manifest when running deeper into the carb.and at higher load settings, as in acceleration.
Pre-ignition however, can occur at any throttle setting, and usually leads straight into detonation. Pre-ignition is when something in the chamber lights the fire before the sparkplug does. When the spark plug then fires, the two flame fronts collide in the chamber, the pressure sky rockets, and you hear it as a rattle. That pressure spike usually breaks stuff, like the pistons if allowed to continue, and can smash sparkplugs. I guess it could also blow the fire rings out
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I have put a couple thousand miles on it since the rebuild and have had no issues with it till I loaded it up for this trip. Was running it pretty hard , 70ish on the hwy was ok till I hit some hilly parts . Sounds like the detonation Yes?
 
dartfreak75 said:
Yea I am further north! You would have to take 77 in then 81 to come pass me!! I cant remember the name of the interstate but 77 turns into something else goes pretty much straight thru Georgia.
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77 comes down threw charlotte nc, on down to columbia sc where it ends near I-20 an I-26
 
dirty white boy said:
77 comes down threw charlotte nc, on down to columbia sc where it ends near I-20 an I-26
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Yea you are right Columbia Is the halfway point that is where we stay when we go to Florida. My brother lives in Florida we go down and visit every couple years.
 
RAT ROD AL said:
I have put a couple thousand miles on it since the rebuild and have had no issues with it till I loaded it up for this trip. Was running it pretty hard , 70ish on the hwy was ok till I hit some hilly parts . Sounds like the detonation Yes?
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Certainly possible, when you list all the factors;
Heavily loaded, hilly terrain,towing,lotsa frontal area pushing air, very high cylinder pressure, pumpgas, hot-running,automatic,
unknown rpm and timing.

There is nothing wrong with running a hi-Scr......... at part-throttle. Because your Ecr (Effective Compression Ratio) is usually still well below the detonation limit of the pumpgas you are using, and at the rpm and load settings being experienced. But as the load increases, you have to increase the throttle opening to maintain speed, which increases the Ecr, which might or might not still be below the detonation limit of the gas.Eventually tho, if the carb size is big enough, the detonation limit will be found.
This limit can vary with rpm and load, and timing.
It is possible for an engine to approach the limit several times throughout its rpm band. It is possible to ease the level of detonation with performance gearing, or to keep it in detonation with too low an rpm , or to put a bordeline engine into detonation with too-high a water temperature, or with a head that cannot shed heat fast enough, or with a poor chamber design, or too much timing.

So yes, before you bolt that head on, you probably want to recalculate the Scr, and more importantly, the Dcr which will require you to know the ICA (Intake Closing Angle).
Dcr is what the engine sees..... at WOT.
Scr is how we build the engine to achieve that Dcr.
Ecr is what the engine sees at any/all throttle settings other than WOT. It varies on a moment to moment basis with load,rpm,air density, and your bolt-ons.
That last one is very important. The root cause of Detonation is too high a temperature in the chamber. Remember that only about 1/3 of the energy in the combusted fuel makes it to the road. Another 1/3 goes out the tailpipe as heat, and the final 1/3 goes into the cooling system, and into the airstream as heat.
So you have several ways to deal with detonation, in a combo that is predisposed to it.
If you put a tiny carb on a hi-Dcr engine, the load might never get high enough to spawn detonation. Or if you put headers on it and a free-flowing exhaust perhaps that exhaust system will get rid of the heat fast enough to allow a bigger carb. And last is the cooling system; bigger is always better, and remember that the thermostat sets the MINIMUM water temp, and limits the coolant circulation by the size of the effective area around the pellet mechanism. And don't forget; tha automatic is pumping heat into the lower tank, sending it's heat straight into the waterpump.
And of course ignition timing. But this is a two-edged problem.Taking timing out reduces the power, and the engine has to work harder, creating more heat, possibly putting the engine into worse detonation. Sometimes more is less; more timing might create less heat.
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I like as much cylinder pressure as I can get away with because it makes the engine much more responsive when transitioning from one output level to another, and because the engine is more efficient, burning less fuel at steadystate, and because it makes more power at part-throttle settings.
But the key is getting away with it.
I build my personal engines with what I always think is too much pressure, and am prepared to run an anti-detonant injection system. So far I haven't had to .
The cam's ICA for me, has been the pressure relief system, for the most part.Also; a lightweight car with a big engine and easy gearing, and a total lack of traction reduces the load drastically.Plus My engine operates at 930 ft plus/minus about 100 ft ; I live on the prairies. This makes the tune easy, and limits the load. The manual trans puts no additional heat into the cooling system. The easy gearing lets the engine spool up faster, reducing the chance of detonation. Twin full length 3" pipes take care of the exhaust heat. And the cooling system is Rock-solid. And the engine gets cool fresh air from outside the engine compartment.All these efforts plus aluminum heads allows my engine to live at 185psi and more, on 87E10.
 
I wish I had something positive to contribute.

I guess if it was me I'd carefully check the block deck and head surface for flatness. Check the fit of a new head gasket and give it another try. A lean condition is not good.
Sounds like you pushed the little engine pretty hard with sustained 70 mph cruise, pulling a load through hills and she got a hernia. I did that lifting a refrigerator by myself.

What rear gear are you running? 2 of the race car tow vehicles at the Clay City race were slant powered so it can be done.

I'm really surprised Big Daddy didn't throw a 392 Hemi into it overnight.
 
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