Featured Technical Boiling over,,,,,,, trouble shooting

Has the system been open for a period of time? When I re***embled my chevy after a long sleep I had to remove a handful of acorns that a mouse had stored in the radiator. Maybe a mouse made a nest in there.

 

Fan is incorrect . And I suspect vacuum advance is not operating as it should

 

I'll stick with the timing and raise you an air bleed valve on the zipps riser. If the water pump is sitting in air its not pumping anything. And I'm unsure of the heater hoses, thinking one should be blanked and the heater fed from the intake?

Chris

 

Sometimes it's obvious, sometimes not. As the pressure in the cylinder under combustion is very high it doesn't take much of a leak to push exhausts into the cooling system. It's harder for coolant to go the other way so there may be little or no white smoke from a small leak.

Hopefully it's a simpler problem, there are plenty of such possibilities, but keep the head gaskets somewhere on the list of possible suspects.

 

Where is the temp sender mounted? in the head or manifold? They will read hotter in the head.
Is the pump above the coolant level like Chris mentioned above?
Did you bleed the air out as you were filling the coolant?
The fan has nothing to do with engine warm up till the thermostat opens.
You have a coolant flow issue.
Never having a riser, I can't say one way or the other what's right or wrong, so check for restricted openings, proper pump rotation, faulty thermostat, air pockets, timing, fuel mixture, and restricted exhaust.

The fan needs corrected, but it's not causing a boil over in 4 minutes.

 

T-stats, I dunno. Can't see coolant moving. Walker has a 90 degree elbow.

The system has been "open" for the ususal time, of power washing/flushing, fitting ***embly, etc. During the years of build the system was "closed" but empty. I added coolant (a-freeze and distilled water 50/50) here last year when I had sure everything was fitted correctly, NO leaks. Only on 1st and 2nd startups I had leaks.

As far as "critters" doing any damage over the years. It's possible, but highly unlikey. I have a couple of snap traps hidden and have only caught 3-4 mice over the past couple of decades. Usually the "bate" on the traps goes stale, hardens, whatever. And has to be cleaned and replaced.

For about 5-6 years a stray cat had wanderd in the garage one day and plopped down on a cushin I had in one of the stools. So I set up feed bowls and a box with that cushin to sleep in. So I quess in that time it took care of an unwanted critters sneaking in.

 

The dizzy advance hasn't nver been hooked up yet. As I mentioned, it's only been started twice. Once in April, for around a min, then last week around 4 min.

The advance on the dizzy is working. When I made the distributer, I had a guy with a Sun machine "check it out". (Post on here about holes in the bottom dist housing)

 

Temp sender is in the place provided in the intake manifold.

,,,,,,,,,,, pump above the coolant level,,,,,. Please explain. The radiator filler neck is highest,,,,,,.

I drilled a 1/8" hole in the T-stat. "Did you bleed the air out as you were filling the coolant" Please explain this "process" of bleeding air. I have never "knowingly" bleed any air out of a cooling system. Since the '60's, I have filled the systems, ran, checked fluid level, went on or topped off. This is the FIRST time I have any any problems on start up.

 

Test the T stat in a pan of water on the stove. They can be bad right out of the box.

 

Like I said, I have never had a water pump riser, but Chris mentioned them having a bleed screw, so maybe it has air in it, maybe not. Try jacking the front of the car as high as you can to get any air out of the block and heads. Since this is a new build, total coolant amount maybe not known, so you don't know if it's full or not. 4 minutes is really quick to boil water, somewhere in the engine is getting very hot very fast. The 1/8" hole in the thermostat should have let any air out as long as it's higher than the back of the heads. Pulling a vacuum at the radiator cap will pull air out if it has any.

Was the motor tight when its was built, meaning hard to turn over? Rings and cylinder wall finish can make them really hard to turn over and create a lot of heat.

I've had an inline six for 26 years, changed water pumps once in all that time due to a seep out the weep hole, they seem like good pumps. I would look at the riser for a restricted p***age way or poor gasket match.

 

Looks like a very clean install and build, post a picture of the front of the engine and radiator.

 

This is the bleeder.
Note, not all riser have this for some reason.

As you can see it’s high. You open the bleeder so trapped air escape’s so water pump impellers will be completely wet.

 

Found an old pic in my phone of the unit I have. No bleeder.

 

Your fan is pushing, not pulling. Like was mentioned earlier, put a piece of paper in front of the radiator and if it sticks, the fan is pulling air through correctly. If the paper falls away, the fan is pushing.
Now as to the thermostat. When I first started up my sbf after a complete rebuild, it heated up quickly and went over 220 degrees in a matter of minutes with the headers starting to glow! Of course I shut it off immediately and pulled the thermostat, which wasn't opening at all. Then I re-***embled without the thermostat (which I had checked in a pan of boiling water - it opened but should have opened sooner than boiling). I also put a fan in front of the radiator to help cool down the motor. Once the engine had some run-in, it ran cooler. Tight engines will always get hotter quicker, but after 20-30 minutes of initial run-in time at around 2,000 rpm, should start to fall back to normal (180-200 degrees) if the rest of the cooling system is functioning correctly.
I really think your fan is wrong. Flipping it and shimming it won't fix the problem. Get a fan that pulls, not pushes, and a spacer that brings the blades within a half inch of the radiator. If that isn't enough, install a shroud and pull air through the entire radiator, not just in front of the fan.

 

You may want to drill and tap a bleeder hole on the top of the water pump riser to let the trapped air out.

 

That's how I understand it. Apparently the earlier risers didn't have provision for a bleeder and drilling / tapping for a bleeder was the necessary fix. I understand later risers had this already done with a boss cast in too.

Simple hole for 1/8npt tapping and hardware store bleed valve. Nothing fancy or exotic.

No amount of filling the rad is going to get trapped air out of that high spot.

Chris

 

To be clear...when you said you had leaks on your first start-up...what was leaking? Coolant, oil, air...and from where?

 

Like said a lot already ,fan is bolted on backword,just turn it over,but also dose not have shroud=works about 1/2 as good with out a shroud.

 

During WW2, Libby Gardener, the finest WASP, ( Women's air service pilot) who flew Martin B-26 aircraft as a ferry pilot, she has some very good time tested information and good advise for you,
@Annette Chaplin your results may vary greatly, but I know that Libby was a very wise woman!

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Fuel leak at the bottom fuel pump outlet. There is no 1/8" to 3/8" flair, 90 degree br*** fitting available. So I made one. (sigh) I quess it didn't work right. So I remade the bottom stainless line, different fitting. 2nd start up fuel leak at the carb fitting. Re made that stainless line. Fuel leaks fixed.

Slight oil leak at the front pan rolled lip. One piece rubber oil pan gasket. Installed as instructions, dry, (againse my better judgment) Took it off, got another one piece gasket. Sprayed it both sides with my usual "High Tack" Gasket spray I have been using for decades. 2nd start uo NO oil leaks.

1 st start up Steady drip out between the bottom hose and bottom radiator inlet. Motor running only leak. No leak with motor off. The bottom radiator inlet shape was expanded incorrectly. I'd have to draw a picture showing what I'm describing. It would seal with one of those ugly worm drive band clamps, but not a crome plated re-popp Ford style radiator clamps, I am using. Talked with Johnson Radiator, (They took over Walker) about the misshapen bottom inlet. Ok, stop here. Vernon Walker used br*** instead of sodder. So a regular radiator shop could not fix or work (screw up, his words) on his radiators. Johnson wanted $800 (!!!!!!!!!!! Whole new radiator was $1,200!) to replace that bottom inlet!!! Not counting the shipping to and from Alabama! So I went to a bend-it-up exhaust place buddy who is a car builder. Took an old bed frame made a jig to hold the radiator straight on and bolted solid with the expander on his pipe bender. (took all day to make the frame jig to get the angle and height) Next day gently re expanded the correct shape on the radiator inlet. As you see in the picture, it worrked correctly! NO leak there on the 2nd start up! However,,,,,,,,,,,,,,,,,,,,,, 2nd start up, very small drip comming from the water pump area. (I'm guessing the weep hole in the pump housing) Can't actually see it up in there where it's actually comming from. (why I mentioned getting one of those 1777CW High Cool water pumps)

In the months and headachs trying fix all these leaks, I hope and pray I don't have anymore!

 

Yesem. Already planed to do so up there towards the end of page 1! Waiting for help here after bit to left the radiator out of the frame, to access the pump, riser.

 

Wonder if she knew "Wrong Way" Corrigan?

 

In the 1990’s, Chevrolet built some “reverse flow” water pumps that spun backwards. I’m guessing you may have a fan intended for one of them. Make sure your photo is not reversed though, that is possible too.

 

Trust me on this kiddo, indeed she did, and for that matter, anyone connected to the insane world of aviation, dam sure knew who " Wrong Way Corrigan" was !

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By the way kiddo, if your going to use that generic ? mark helmeted dude for your avatar, I suggest you take advantage of the original image, where that ? mark dude came from!
Thanks from Dennis.

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First, for the sake of clarity . . . Everything I'm seeing online seems to indicate that engine and fan rotation is correctly designated as clockwise or counter-clockwise as viewed from the back of the engine.

Then, if somebody can tell me if I'm just blowing smoke or not. If the fan is installed backwards it may still move air in the right direction, but not as effectively as if it's installed correctly. The pitch of the blade is still correct. But inverting the curve of the face of the blades affects its efficiency.

The only ways to change the direction of airflow is to reverse the fan's rotation and/or change the pitch of the blades.

So could the OP's problems possibly be caused by a mis-match of parts as mentioned above between old and new style SBCs? Standard or reverse cooling? Serpentine or v-belt accessory drives? Different reverse cooling water pumps? Different fan blades? I think maybe the later engines' heads had a couple extra coolant or vent holes and used different head gaskets. It's a more complex set of changes than many people are aware of.

 

Question. The Flow-Cool water pump 1777CW will fit the Zippy riser with no problem, correct? Thanks

 

From what I see, it's a small block with a water pump riser using a standard inline six Chevrolet water pump. The fan blade is on backwards but will still pull air the right direction, just not as efficiently as it would normally.
I don't believe any of the 250-292 inline sixes used a reverse water pump, by the time the serpentine belts came around the inline six was out of production in the main stream.

 

Standing at the front of the engine an automobile engine will be seen turning clockwise. Some boats will use both, a CW and CCW engine to prevent a twin screw boat from being steered by the props.
The lack of a bleeder to clear an air lock in the riser has been mentioned but never addressed by the OP. I don’t see one in the photos provided so I’d correct the fan and add a bleeder if in fact there is none. As far as the heater hoses go I don’t think it really matters much. Some heater cores will have different sizes, a 5/8” and a 3/4” hose ****** and on an OEM installation the water pump and intake manifold hose ******s would be sized for their respective hoses. Hot rod installation? Take your pick, I can’t see either way making a lot of difference. You said the engine has been run but the vacuum advance hasn’t been hooked up yet, as simple as that is to do I’d connect it and also check the initial timing with the vacuum hose disconnected and plugged. Too little initial will cause the engine to run hot. Oh, and I like to connect the vacuum advance to manifold vacuum not spark ported.

 

Mechanicals have been covered pretty well. What’s alarming everyone is how in 4 minutes time from a cold start it’ll push water out. I think one member touched on it?

Is there an exhaust gas issue happening where exhaust gas are getting into the cooling system and over pressurizing it?

Point being, always test before throwing money at a problem.

 

Took my old 6 cyl pump off. I had added a plate on the impeller to help it pump. The pump was cast iron. Bought the aluminum flow master. All works fine. But I run 5 degrees higher temp. You must bleed the air out. I used a pump for leak testing. Pump up let set. Bleed off several times no air trapped. 100 degrees outside temp. Driving in town with air on temp is 185-190. Stop climbs ro 200. Cools back down. 6 blade fan with shroud from Walker.