[hotrod4dr55]

After 2 years I finally finished up my engine and got it in the frame and fired up to break it in, but I cannot keep coolant in the radiator or it from overheating. The engine is a 1982 350 block with 906 vortec heads. The shortblock and heads were rebuilt with beehive springs installed. I have also drilled 6 holes in the themastat for bypass issues. I have bypassed the heater hoses by connecting the water pump to the passenger side of the intake as shown:

https://plus.google.com/u/0/photos?tab=mq#115572865768867314195/posts/TY6JmHmhq7t?pid=6127635058459368978&oid=115572865768867314195

I'm hoping it has something to do with this routing being incorrect. The main issue I have is it runs for 10 minutes or so and then starts to get warm and blows water and steam out the radiator....and not just a little. The water pump and radiator are new. I fear I may have a cracked head, but it is not just bubbling...its is blowing water like a geiser like it has huge air pockets.

Any one have any ideas to go from here? Radiator pressure test? Pull the plugs? I know you can get the kits to test for gas fumes in the coolant from Napa, but I cannot keep coolant in it to even do something like this.


In addition, I've noticed the passenger side exhaust being warmer than the driver side because the stainless exhaust clamp has turned colors on the passenger side and the driver side still looks new. I initially just thought it had something to do with the cam break-in, but I'm now wondering differently. Should check it with a infrared temp meter or something?

Thanks in advance for any ideas, suggestions or information. I'm stuck at this point.

 

[mouse_zzr600]

UMMMM same issues here. You reading my mind..
I found so far my thermostat (although new) was faulty. It was intermittent with temps for the opening and closing. However it did not fix my issue. My water pump is next. Just fyi i have heard that the pressed steel impeller can expand at a different rate than the pump shaft and cause a slip at operating temps causing no coolant flow. Mine is cast so back to the drawing board for me, I may need to replace anyway as the bearing is a bit noisy and i have a slight leak from the weep hole .
You may want to try that first and see how you go..
Hopefully you have better luck and it is just that..
As a side note a way to check if you have a cracked head or coolant issues in a particular cylinder is this inexpensive way (time consuming though).
1st:- Get yourself 8 short screwdrivers approx 6" (does not matter on phillips or flat just 8) Spark plug socket and wrench and have them handy.
2nd :- Get engine up to temp, about 5 mins (not that hot to start the geyser effect) and shut down. Disconnect battery ( just to be safe you do not turn key on and try to start)
3rd :- Remove the spark plugs (being careful to not burn yourself or mix the firing order of the plug leads.
4th:- Insert carefully screwdrivers in the plug holes ( 1 per cylinder)
5th :- walk away for 5 - 10 mins.
6th :- Remove screwdriver 1 cylinder at a time (careful they will be hot) and see if the screw driver is wet with condensation. If it is then that cylinder has a coolant leakage issue.
Once identified (if at all) you have an issue then you can progress from there to do what ever repairs are required.
Hope this helps David.

 

[puzzley]

Many RamJet /vortec engines have cooling problems, as outlined in this thread:

http://www.trifive.com/forums/showthread.php?t=59036

It's certainly worth a read.

 

[rayharris]

Replace the thermostat. :anim_25:bowtie-trifive:gba:

 

[hotrod4dr55]

Thanks for the responses and suggestions. Regarding the thermastat, I've pretty much ruled it out because I initially thought this and I've put a second thermastat in it and drilled holes in the second one and it got not better. I've also tried running it without a thermastat trying to make sure I wasn't somehow making an air pocket. I went through and read the older post on ramjets and vortec heads and it doesn't appear to me that bypassing the heater with a hose from the passenger side intake and water pump is a problem. If not, I think I have bigger issues.

Last night I pulled the passenger side plugs. All the plugs are new, but have run enough to break-in the cam so they have a slight tan color to them except #4 is bright white and looks brand new. I'll have to pull the driver side plugs next and see what they look like, but from what I've read the vortec heads are prone to cracking on the middle cylinders, so this seems to be adding up.

Does a radiator pressure test bleed down if the head is cracked? In addition, if I have to pull the heads would it be ok to put just one head on it as long as I get another 906 vortec head? They both were reworked, but even if the driver side plugs look okay should go ahead and pull it too and have it rechecked?

 

[techman441]

my suggestion is to pressure test the radiator after the engine has been warmed as much as possible,with all the plugs removed if a cylinder is leaking, steam will exit the spark plug hole...and remove only the bad head...

 

[Pops @ Tri-5.com]

I believe engines with Vortec heads need a bypass hose, like shown in the photo below.....See link: http://www.trifive.com/forums/showthread.php?t=59036

Here's a clip from the instruction manual..and yes it is a 350
"Water Pump:
The RAMJET 350 engine includes a standard rotation water pump. This is a cast iron, long leg water pump; the same pump that is installed on the GM Performance Parts ZZ4 crate engine. Any small block engine, regardless of year, that uses Vortec heads, will require an external coolant bypass line from the intake manifold to the 5/8" hose nipple on the water pump (passenger’s side). Suggested routing is from the 3/8 NPSF boss on intake manifold to the water pump."

"Engines with thermostats don't allow any water to move in the front of the intake if you don't run a bypass. The water gets very hot in the heads during warm up and since the water is not moving, the heads just keep getting hotter and hotter until enough heat wicks up to the front of the intake/thermostat and allows it to open. Thermostats open and close during engine operation and what will happen is that the temperatures in the heads will swing wildly and not as well controlled as it will if you DO run a bypass. The internal bypass in the older blocks is only on one side because that is all you need to let the water move.

I can tell you I have fixed MANY Vortech headed engines that have radical temp swings by adding a bypass to the front of the intake. It took me a while to figure out why that works but I know it has in more cases then I can count."

 

[cruzn57]

what water pump are you using?

are you using a serpentine belt system?
is there a possibility that your water pump is running backwards?
as late model pumps turn backwards from older std pumps.

 

[acardon]

The lack of a bypass hose won't cause the symptoms discribed. I ran my Ramjet for months with no bypass and the heater connections plugged. Sorry to say, sure sounds like a blown head gasket or cracked head. I don't think I would want to do it on a engine that hasn't been broken in, but if it is a blown gasket, you can find out which one by pulling the plug wires one at a time, while running, and see which one stops the steam.

 

[hotrod4dr55]

Thanks for all the advice. I just bypassed the heater with the hoses connected like the photo shows and from the other comments it appears that is not a problem. I'm running a standard SBC March pulley system with an older longer water pump too. So, sounds like I need to start looking into the heads further. I'm going to pull the plugs on the driver side and I hope they look good....I'll no doubt be looking into at least the #4 cylinder.

 

[Muscleparts]

are you using a serpentine belt system?
is there a possibility that your water pump is running backwards?
as late model pumps turn backwards from older std pumps.

Might want to check this, I got the wrong one in the right box before. only thing different is the impellor I believe.

 

[1mean5-7]

I went from an original 7 lb cap and went with a 13 lb and all my cooling troubles went away..... i keep an eye out for pressure leaks on my radiator but no issues yet with 7 lb cap it over heats and spews coolant in a matter of minutes...13lb cap and hottest it will get is 195°

 

[tmoble]

got this fixed yet? any update?

I'd rent a radiator pressure tester from one of the chain stores. disconnect the battery, pull the plugs, pressurize the system to 15 lbs and wait. if it bleeds down pump it back up. if there's a cracked head or other containment issue water will run out of a spark plugs hole eventually. leave the battery disconnected, you don't want anybody cranking the starter at all, even with the plugs out. if a cylinder hydraulic locks there could be severe engine damage. you're already in danger of that if it's leaking into a cylinder and you're starting it up.

Anyway, let us know your findings.

Were the heads new? rebuilt? used?

 

[hotrod4dr55]

I have not had a chance to mess with it....my son plays on two baseball teams, so spring gets hectic. I'm planning to do as some have suggested and pressurize the system with the plugs out and see what happens. The heads were rebuilt, not new.

 

[crankshaft]

Sure sounds like a `blown head gasket.

Just pull all the plugs and leave overnight. The next day should show evidence of water in the bad cylinder when you crank it over. Place shop towels in front of each hole before spinning it over.

 

[airmentbob]

you can always pull the cap on the radiator and run it, you'll be able to see if the water from the radiator is moving. just a guess.

 

[hotrod4dr55]

Long overdue update

Well, I finally got back to looking at this engine. Many months ago I pulled all the plugs and pressure tested the radiator and it held fine, so I put it up and haven't looked at it again until last week.

So, after many months I just went ahead and pulled the heads. I quickly noticed that the #3 cylinder was clean without any carbon. The head gasket was the Felpro 1094 .015 shim and looked fine, but it's hard to read the steel shim style gasket. So I looked at the heads and they visually looked fine, so I took them to the machine shop to have them checked.

I talked to the machine shop and told him about the geiser that was coming from the radiator and that #3 cylinder had been steam cleaned. I gave them the old head gaskets and he couldn't really see any signs of failure either. I fully expecting to have a cracked head...I think they did too. They magnafluxed and pressure tested them and just called to say the heads tested fine, but they needed to be resurfaced.

I told them to go ahead and resurface them. I must say I'm a bit nervous to use the thin .015 Felpro 1094 again at this point, but it is ideal for quench. I did notice it looked like whoever put the heads on used ATV vs. thread sealer. This may be acceptable, but I've always used high temp thread sealer.

 

[Typhoontx]

I've always used permatex # 2 on the head bolts , not had any issues leaking, but a leak around the head bolt as far as I've seen won't cause the issue your seeing of coolant blowing out the radiator , water in the oil or dripping around head bolts on the outside edge of the head are what you see when head bolts that go into the water jacket leak.

On steel shim gaskets I've always sprayed them with copper coat sealer on both sides

 

[hotrodg726]

do not use the shim gasket . FEL-1043 is my go to head gasket for small blocks. the shim gaskets require everything to be perfect including the surface cut. I have never had a 1043 fail. I use arp thread sealer on the head bolts.

 

[Lilracr]

What is the details on the water pump? There is a reverse flow pump that was used with the serpentine set ups.