Main and / or rod bearings failure in 1968 DVC

[cadillacmike68]

Thanks Bobby,

It only creeps when I'm stopped in heavy traffic. As soon as I get moving it goes right back down. I'm thinking of of putting an engine oil cooler in to 1: add more oil to the system, which helps dissipate heat, and 2: to get the oil a little cooler inside the block which will also help. I don't think I'll add a transmission oil cooler since I put in the Derale pan with the 10 vent tubes in it.

[Bobby B]

Thanks Bobby,

It only creeps when I'm stopped in heavy traffic. As soon as I get moving it goes right back down. I'm thinking of of putting an engine oil cooler in to 1: add more oil to the system, which helps dissipate heat, and 2: to get the oil a little cooler inside the block which will also help. I don't think I'll add a transmission oil cooler since I put in the Derale pan with the 10 vent tubes in it.

Mike,
  Try and find the root of the problem (if there actually is one), before you add some additional aids. They might just mask your issue so you'd never know what was causing the problem in the first place. Whenever I troubleshoot a problem, I'll only change one thing at a time until I nail it, and go from there.
                                                                                                                                                       Bobby

[35-709]

RE: Your hood.  Read Greg Surfas' reply in this thread ---
http://forums.cadillaclasalleclub.org/index.php?topic=115599.msg186743;topicseen#msg186743

[cadillacmike68]

Mike,
  Try and find the root of the problem (if there actually is one), before you add some additional aids. They might just mask your issue so you'd never know what was causing the problem in the first place. Whenever I troubleshoot a problem, I'll only change one thing at a time until I nail it, and go from there.
                                                                                                                                                       Bobby

Bobby,

The owners manual says on p10: "The gauge pointer will move from C to the one-quarter mark. Do not be alarmed if the pointer registers above the center range in heavy traffic or on long drives during warm weather. The pressurized radiator will prevent coolant loss up to 259 deg F..." It then notes the engine metal temp warning buzzer and red warning lamp and to shut if off it those go off.

It's done exactly that, crept up, but not to the point where it sets off the light and buzzer. Moving along even at highway speed in 95-105 deg F weather has not caused it to register hot in the past, and on cooler days with the top down the pointer will actually settle below the 1/4 mark. Heck on Dec 30 last year the pointer was at about 1/8, that's how cold it was outside.

I've also put in the 1969-70 overflow tank and RC-27 cap so it it ever blows some coolant out, it will be recovered.  It did not and does not leak coolant.

I keep the concentration at approx 50%, for the best balance. I also use water wetter, but that doesn't seem to do much.

My main concern is not ruining the expensive rebuild job by cooking the bearings. The traffic today is MUCH heavier than it was 50 years ago, and its HOT down here; 95-105 temps in the summer with the asphalt temp getting to 130-140+ degrees, that's hot and that's the air coming across the radiator in the summer when you are stopped in a mile plus long backup with hundreds of cars putting out all that heat. And if the top us up, the Climate Control adds to the engine load.

That said, I looked carefully at the engine when it was apart and the bearings and I saw No indication of overheating causing bearing or any other damage.

Yeah the starter got cooked, but I put a shield on, it probably won't help since I got it on with the wrong angle of the dangle, but I can move it or add a second one, or wrap the starter, and now I have two spare starters.

So do I just leave it alone or take some measure to keep it a little cooler?

More quarts of oil in the system will take more heat away from the engine, that's a function of physics. A little air across it will help more and the thermostat will prevent the car from running too cool, so an oil cooler system can only help - unless it leaks of course.

In which case I'll probably rig up a bypass connector to eliminate the cooling lines and keep it with me in the trunk. along with a spare oil filter. Sort of like my 48" belts in case the compressor seizes, the little jumper in case the neutral safety switch breaks and the little jumper in case the Climate Control goes out of control and refuses to turn on the fan...

RE: Your hood.  Read Greg Surfas' reply in this thread ---
http://forums.cadillaclasalleclub.org/index.php?topic=115599.msg186743;topicseen#msg186743

Thanks! I'll try this when I can get someone to help with holding / propping the hood.

[Bobby B]

Mike,
Hi. Sounds like you have all the bases pretty much covered. Is the timing dead on and the carb mixture perfect? If you don't hear any pinging under load, I wouldn't be too concerned. Just for ha-ha's, you might want to get a cheap gauge to double check the temperature, if you say it's not setting off the light/ alarm. I'm not familiar with your cooling system, but does the fan have a clutch or is it a full time fan? Electric fans? I know that feeling of driving "scared' all the time. I was big into Pontiacs at one time, and they tend to run way hotter than anything else out there. The running temperature of High performance Pontiac 400's would put most people into panic mode, but it's just the way they run. Today's fuel isn't any help either. I fought an overheating problem with the '47 Flathead for years until it finally gave up. Valve seat and cylinder wall cracks were the culprit. I think you're just being overly cautious and a little nervous with your new motor, and that's understandable. Don't sweat it, it happens to just about everyone who's had their engine rebuilt. The break-in period is quite nerve wracking to say the least...
          Bobby

[cadillacmike68]

Mike,
Hi. Sounds like you have all the bases pretty much covered. Is the timing dead on and the carb mixture perfect? If you don't hear any pinging under load, I wouldn't be too concerned. Just for ha-ha's, you might want to get a cheap gauge to double check the temperature, if you say it's not setting off the light/ alarm. I'm not familiar with your cooling system, but does the fan have a clutch or is it a full time fan? Electric fans? I know that feeling of driving "scared' all the time. I was big into Pontiacs at one time, and they tend to run way hotter than anything else out there. The running temperature of High performance Pontiac 400's would put most people into panic mode, but it's just the way they run. Today's fuel isn't any help either. I fought an overheating problem with the '47 Flathead for years until it finally gave up. Valve seat and cylinder wall cracks were the culprit. I think you're just being overly cautious and a little nervous with your new motor, and that's understandable. Don't sweat it, it happens to just about everyone who's had their engine rebuilt. The break-in period is quite nerve wracking to say the least...
          Bobby

Bobby, I have a Fluke infrared temp gun, and in 2016 when this was giving me grief we temped it, while hot. The coolant was coming out of the upper hose at about 210-220 degrees and going across the radiator it went down to about 140-162 just before hitting the right tank, which then jumped back up to 180 or so because the trans was also hot. So the radiator cooled ok. Not completely scientific but it seemed ok. I'll check it again now that I have a re-cored radiator this weekend after it get it heated up.

It had the original 1968-69 style 7 blade clutch fan but that was routinely checked and supposedly never was bad. I changed the clutch and fan & a half a year ago, because my fan blades were bent / curved??

But I took it off and have a 1970 style 7 blade no clutch fan in it now. Belt driven fits right on the water ump. No electric fans, but I was considering a pusher fan once, but that's way too ugly looking.

Carbie. It not lean, might be a tad rich. Too lean will make it run hot.

Timing. That I have to look into much more closely. I need to remember to get an adjustable timing light.  There is a tightrope that needs to be walked on these high compression 1968-70 engines. Too little advance and it runs hot, too much and it knocks all over the place.

There was No evidence of damage due to spark knock when it was taken apart, and I run only Shell premium 93 (which still isn't high enough) and then I add in some Sunoco 110 octane to get the octane up to 95 - 96 or so and there's no knock. If I don't have enough 110, I can hear / feel it on med to strong acceleration.  I also have a crane cams adjustable vacuum advance.

One can't time these engines to a fixed "12 degrees before", or "30 deg total advance" etc. One should start at factory specs and then make any adjustments to vacuum or mechanical advance which doesn't even come into play with factory settings because timing adjustments are to be made with the vacuum advance disconnected and plugged. The spec is 5 degrees BTDC for a warmed up engine at 600RPM in Drive.

Where the adjustments come in are the springs for the mechanical advance and any adjustment of the variable advance on the crane cams advance - After the initial setting is correct.

It's going to be a complex endeavor to get timing just right, not because it can't be brought to original factory specs, but because of the crappy a$$ed gasoline we have today.

[Bobby B]

Mike,
Just a stupid question....Does  that car have a fan shroud? If you replaced the fan clutch with a "Solid" mounted fan, Did you use a spacer to keep the same distance from the Radiator? The blades need to be a calculated distance within the shroud for optimum cooling. Datsun 240Z's suffered this problem because people would remove the fan shroud and discard it. When I got mine it did the same thing, and it was an original California Car. Once I installed a repo fan shroud, the temps went down a good 10+ degrees. You also mentioned the Crane system. You need to make sure that it's operating properly. I'm so leery of todays aftermarket parts. The spike thing it's what's confusing me. Temp spiking is usually associated with a blown head gasket, air in the cooling system, or a slipping impeller on the water pump, and/ or an impeller with the improper clearance to the pump body, allowing cavitation. I would also pull the Stat and toss that baby in a pot of water on it's way to a boil and check what temperature it's opening on. I test every thermostat before I install it in any vehicle. Might want to throw an old radiator cap on there also to see if that would make a difference. It's a tough problem (if there actually is one) to chase......
                                                                                                                                                                Bobby

[cadillacmike68]

The original fan shroud is in place and I have the 1970 no clutch fan spacer installed. The new fan is about the same size as the old fan, less than 1/2" clearance between it and the shroud. I'm not new to this, I've had this car for 20 years and back in the late 70s early 80s had 3 others of the same year range.

It's not temp spiking. It creeps up when stopped in heavy traffic.

And as I noted before, while moving the temp will settle back down to where it belongs. The Tstat is new and the water pump, a flow-kool one, only has about one year of use so I put it back on.

The manual says not to be alarmed, but I just don't want to have to rebuild it again in another 5-6 years.

[Scot Minesinger]

Mike,

After reading this, and your suffering with a shop that installed the engine - it just reinforces how important it is to see it done right.  The actual remove my engine after everything is ready for the pull - 1/2 hour tops.  Reinstall engine in place secure to trans and front mountings - an hour, and that was my first time.  Plus none of this BS.

Understand not many have space and patience to do this.  However, what I take away from this is ask how much extra it will cost to have me their supervising the work or helping - usually this cost is double normal but apparently well worth it.

These 472 engines are very sensitive to overheating with bad timing.  Even five degrees retarded will cause it to run much hotter than it should.  Another thing I see is distributor is a tooth off - if you check timing yourself and do not see the mark - it is that.  Obviously you already checked heat riser, no big gaps between radiator and sides/bottom, and etc.

When you get it dialed in, it will be amazing!

[cadillacmike68]

Mike,

After reading this, and your suffering with a shop that installed the engine - it just reinforces how important it is to see it done right.  The actual remove my engine after everything is ready for the pull - 1/2 hour tops.  Reinstall engine in place secure to trans and front mountings - an hour, and that was my first time.  Plus none of this BS.

Understand not many have space and patience to do this.  However, what I take away from this is ask how much extra it will cost to have me their supervising the work or helping - usually this cost is double normal but apparently well worth it.

These 472 engines are very sensitive to overheating with bad timing.  Even five degrees retarded will cause it to run much hotter than it should.  Another thing I see is distributor is a tooth off - if you check timing yourself and do not see the mark - it is that.  Obviously you already checked heat riser, no big gaps between radiator and sides/bottom, and etc.

When you get it dialed in, it will be amazing!

Scot,


I didn't have the space, equipment, knowledge, etc. to get it out  and back in.

I was there a lot while everything was getting done, and I bought most of the parts. The only parts I didn't get were cam bearings (which I would have if they had told me it needed them beforehand) and and some plugs, but they got the exact same ACDelcos that were in the car. I even painted the block and a lot of small arts (of course the valve covers got all smudged up with re-installation).

Just about everything was done exactly correct, except they fell apart on re-installation. They Weren't paying enough attention, etc. etc. etc. It's not really the worse for wear, Speedo is working fine, Twilight Sentinel; I'll have to research that, but I hope it's a misplaced sensor or wire.

Timing lights:

What are some good brands vs some poor ones? Can I get a decent one from the local auto parts stores (AutoZone, Advance and O'Reillys are around here).

[Highwayman68]

Twilight Sentinel; I'll have to research that, but I hope it's a misplaced sensor or wire.

Mike, if the dash cover was removed then start there. The sensor mounts near the speaker. If it was forgotten about during reassembly then it will be laying somewhere close below the speaker. It is dark brown about the diameter of a dime.

[cadmium]

I don't think I've seen this mentioned here unless I've missed something.  About your temperature creeping issue, have you checked to make sure the shop installed the correct thermostat?  This engine takes its own style thermostat and while the standard GM thermostat will fit and give no indication that it's not right, coolant will not flow properly through the block and the engine will tend to run hotter than it should for no apparent reason. 

[35-709]

Guess it hasn't been mentioned in this thread but it has been discussed on these forums before and I have posted pictures of the correct 501 series engine thermostat before as below ---

Pic. #1  Correct thermostat

Pic. #2 Lesser GM make thermostat

[cadillacmike68]

I bought two AC-Delco 12T18D stats which look like pic # 1 above, so it is the correct stat.

Again, it DOES NOT creep while moving down the road, even when it's quite hot outside. It only starts to creep when I'm STOPPED in heavy traffic (or moving at 5-10mph on a hot engine).

[Cape Cod Fleetwood]

Mike, this probably means nothing but...
my 2008 GMC Acadia (136K) will creep when I'm stopped or in slow traffic on a super hot day with the AC running. Once I start rolling again it goes back to normal range.
\m/
Laurie

[35-709]

Temp creep on a hot day in stopped or stop and go traffic seems perfectly normal to me --- as long as it doesn't overheat.

["Cadillac Kid" Greg Surfas 15364]

Mike,
Just to chime in here.  The subject of 472/500 inch motors running "hot" has been discussed at length.  These motors WERE DESIGNED TO RUN BETWEEN 210 AND 220 DEGREES in order to obtain the efficiency that the higher temperatures bring.  Less energy  (from the gasoline) is wasted by being removed by the cooling system and stays in the combustion process where it should be. 
That said there is the issue of gages, their necessity and their accuracy. looking at a gage that constantly reads 220 degrees is off-putting to those not used to Cadillacs, and even some of us that are.  That is the reason I don't have any auxiliary gages on any of my "street" cars.  The factory temperature warning lights and oil pressure warning , IF WARNINGS ARE FOLLOWED, are sufficient.
One of the things that these motors need is an appropriate, working vacuum advance for conditions of light load, and in particular for low load, low speed, warm temperature operation.  I even have one on my "hot motor" car, so I can drive it out to the strip and idle in the staging lane without it overheating.
Something on the order of 20 (crankshaft) degrees at idle vacuum is what a stock motor wants.
If your vacuum advance is functional (hooked directly to intake manifold) and none of your warning lights come on, you are probably okay.  Just drive it and get the motor broken in changing the oil at (I do this) 4-500 miles. Use a good oil (I use Valvoline VR-1, 10/30 wt) and change it and the filter at about 3000 miles or 6 months. 
On to the next "project" issuer.
Greg Surfas

[cadillacmike68]

Greg,

So what I need to do is ensure that the base timing at idle, AC off, vacuum adv disconnected, etc, etc, is the specified 5 deg BTDC.

Then adjust the vacuum advance to 20 total degrees at idle (vacuum reconnected of course) -NOT to 20 more than the base 5 - correct?

Then I can experiment with the mechanical advance springs (I think there are like 6 springs in the kit) to give the best performance without knocking.

I have the car set up exactly as it was new. The carb advance and manifold advance are Both connected to the thermal vacuum switch and That is connected to the distributor. I'll have to test that switch as well, but there is a test procedure in the manual, and I have a couple spare thermal vacuum switches.

Now how about a timing light recommendation??

As to the gauge. I'm sure it is accurate enough, and the manual DOES say not to be alarmed, etc... but It cost Plenty to get the engine overhauled, nearly all my extra savings, and I don't want to have to do it again.

["Cadillac Kid" Greg Surfas 15364]

Mike,
If you are going through the thermal vacuum switch for vacuum advance vacuum then I understand why the temperature creeps up.  The switch does not allow manifold vacuum until the motor reaches a bit over 210 degrees.
This is part of the emissions system.
I suggest you do as you say regarding timing and hook up the vacuum advance can directly to manifold vacuum. You can do this as an interim stem to be sure nothing else is causing the motor to run warm.
You talk about "adjusting" the vacuum advance.  I have to take that to mean you are using an "adjustable" can.  I personally have never found them to be the best and have always used the stock, factory can. AC Delco D1346C will give you 24 (crankshaft) degrees at 15.0-17.5 inches of vacuum and start at 8-10 inches.  This is tailored to the engine's requirements, assuming you are still running 10.5:1 compression.
Greg Surfas

[cadillacmike68]

Greg,

Yes I have a Crane Cams adjustable vacuum advance. I'm running slightly over 10:1. K&B pistons specified to be 10:1 with shaved heads. Certainly not 10.5:1 but a tad over 10:1. Essentially the same, too high for today's fuels, even 93 octane shell.

I do have it set up factory spec and can easily change to run the MT directly to the carb and plug the carb vacuum line & fitting.

I see the ACDelco D1346C vacuum advance. There is also a D1359C, costs a bit more and no other explanation, both are in rockauto as fitting 1964-1972 Cadillacs. Is the D1359c better than the D1346, or should I save my $3 and buy a quart of 110 octane gas instead?