Thread: Zips riser

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Don,
You're right on the boiling point around 225F - I misread the chart My point is that even with no cap, you're not getting hot enough to boil so a pressure cap is not going to help here. If you're blowing water from the overflow it can only be from too much pressure, which can only be coming from a spot problem in the engine. I've seen head gasket leaks that only allowed pressure to go one way, and would not leak water into the cylinder or into the oil. I think you're wasting time trying different "fixes" on the radiator. It's not boiling.

I wonder if you're not confusing expansion with "boil over"?? If you've filled the system to the max, then some fluid has to come back out as it expands! Especially if your only at 200 : 205 degrees.

Roger and 34-40,
Thanks for your comments. The cap I was using does say 16 psi which is what Walker recommends. Anyway for the price of $4.71 at NAPA I got a regular cap marked 16 lb. and put that on. I started the engine again and allow me to digress by saying what a thrill it is to just give it a little pedal when I turn the starter key and it "barks" into action! The build is only a little better than a stock 350 at probably only 270 HP but through the turbo mufflers it rumbles great! Anyway timing it again with the air cleaner on it running at only 1100 rpm it warmed up as usual and in about 15 minutes it reached a steady 220 F with the new cap UNTIL (!) the pressure blew the lower connection of the upper radiator hose off! I was using a simple rubber hose so I guess I will get one of those braided hose kits with the special ends but that does not answer the problem as to why it heated up. At a steady 220 F it was probably boiling and the added pressure found the weakest point at a hose connection. Apparently the toy cap with the thermometer in it had a weaker spring than the new cap but if heat continues to build in the engine more than the radiator can handle it will eventually blow some hose or the radiator core unless it reaches the cap release pressure first. Since my 50/50 mixture is only a rough vol/vol dilution I was probably at the boiling point at 220 F and slightly below the 16 psi release of the new cap. Roger may be on the right track about some sort of head gasket leak. I will have to think this over more because I am really hooked on that engine rumble now!
Thanks for your suggestions.

Don Shillady
Retired Scientist/Teen Rodder

Time to hook up the coolant system pressure tester and see where all the extra pressure is coming from!

Don, all due respect but you're over analyzing this one. You have something driving your system pressure way, way up and it can only be an internal leak. What happens if you leave the cap off and watch the water in the radiator? My bet is you're going to see bubbles. Anyway, I think I've added all I can to this one. Hope you get it worked out.

I concur.. Use a pressure tester and see if you can push coolant into somewhere it doesn't belong or at a minimum verify how much pressure is really being created in the system.

Have you checked your oil level? Is it rising? Perhaps after sitting overnight, crack the oil pan drain plug and see if coolant is on the bottom. Just grasping for straws tho'..

I am unfamiliar with a Zips Riser but, are you certain it's allowing coolant flow? Since I'm not familiar with it I am unsure how you could test that the system is flowing coolant.

Thanks all, Clearly the development of my roadster project owes a lot to members of the Club Hot Rod. This is an embarassing situation for me if it turns out that I messed up installing the heads so I will first do a compresshion test on the cylinders to see if I can find a leak maybe on only one bank and then I can replace the gasket on that side using new head bolts. In my car the engine is relatively exposed and I think I can replace a head gasket on one head in a few days if the weather stays warm enough but I am working against cold weather and a cranky sinus. If both banks need a new gasket I may be able to replace one side at a time without removing the intake and resetting the distributor? The engine sits high in the Model A frame and if I lean over the fender it looks like all I have to do is remove the manifold bolts on one side and head bolts without resetting the distributor and then after closing that up do the other side by leaving the intake manifold bolts loose to reset them in new intake gaskets. If the weather holds warm enough I can do this easily in a week or two but if the block is cracked or a head is cracked that will be a different story. I did pay to have the exhaust ports "ported" so maybe one of the 882 heads is cracked? I checked the oil a few hours after the "geyzer" and it is still right on full and clear with no evidence of milkiness so maybe all I have is a head gasket which leaks combustion gases into the coolant? Thanks for a lot of expert comments. Since I am retired I can do whatever it takes to get back to the wonderful rumble of this engine running as long as the weather is kind to my sinuses. Two years ago I had a "garage floor dust" sinus condition that nearly did me in for almost six weeks and I don't want to do that again.

Don Shillady
Retired Scientist/Teen Rodder

It will be very hard to keep the intake gasket in it's proper place without lifting the intake. You may be able to raise the intake "just a bit" and attempt what you are saying... but, imho... it's a folly.

Don,
If indeed you have a head gasket problem, you cannot pull a head without pulling the intake. If you loosen the intake bolts and "lift it a little" you will at the very least break the bond with the gasket/sealant front & rear and will have oil leaks. Worse, you will disturb the intake to head gasket seals (both sides, and you may then generate yet another leak, either vacuum or coolant. The block has alignment dowels to ensure that the head is properly set before bolting it down, and you cannot possibly loosen things enough to lift the head over the dowels, replace head gaskets and drop the head in place over the dowels without any early contact between head & gasket with the intake in place, IMO. The pro "engine guys" may say I'm all wet, but I don't think so.

Suggest you solve one problem at a time. Pulling & re-installing the distributor is not a difficult task if you mark positions before you loosen things. You can even eliminate the need to re-set the timing if you mark & re-install carefully.

Don, Sorry I didn't respond sooner on the shroud pic.

Tom J.. Is that a Zips Riser? I've never seen one.

Yes, it raises the fan about 4" and uses a 6 cyl Chevy waterpump. The pump I used is aluminum from Autozone and is pretty nice.

Thanks for the info TomJ.! I had a mental picture in the back of my mind of what it would look like and I was pretty close.

TomJ.

Thanks for the picture. The '32 shell allows more space than the '29 but the top radius is about the same as mine with a 16" fan. I am waiting for a compression tester I have ordered in the hope that I may find a gasket leak on only one bank. I see no bubbles in the radiator and the oil is not milky but I tried it today without any thermostat and it reached boilover in about 7 minutes at 1100 rpm so either a thermostat does a good job of slowing down the flow or the head gasket problem is getting worse. It looks like I will have to pull at least one head. Today I also bought a set of used 882 heads in case my exhaust porting is the cause of a thin hotspot in the exhaust gallery. I also talked with a guy who has ported exhaust holes for race engines and he said it is unlikely that exhaust porting is the cause of the heat but I now have another set of "used-virgin" heads if indeed I need to replace both heads. I looked at a flow tester at Sears today but with the Zip riser in place I don't see how to use the flow meter. The problem for me is that the weather is getting colder so I may tear it down but end up letting it sit until Spring warmth. Your shroud looks really good, did you bend it yourself?

Don Shillady
Retired Scientist/Teen Rodder