Hooch cooling system pushing out water from cap

[joedrum]

Well bike running ...put two head gasket on ...went for about 50 mile run....let it cool down ...went out and checked he water ...it was full and it started running over top ...then I realized it was siphoning water out of the expansion tank ....so I’m guess that’s ok and would happen as tank is higher than radiator ...learn more tomorrow ...on test ride ...

Ok things I noticed ...ash was really using my thinker today ...one thing is when goo gaskets come off oldwing ...they always look dimpled ...that means when they are made they have harder and not so hard spots in them ...I noticed this when cleaning things up ...so the compression is not even ....because the makeup of gasket not even ..very plain and simple ...the gaskets looked rather good ..they havnt been on very long ....but in the waterjacket area they looked fatter or swelled up some ...so when I squeezed this ..guess what water came out ...water was inside the gasket ...this swell starts dam near at the fire ring ...wow I thought ....well I got things all cleaned up ...I saw signs I think water getting in the cylinders ...but it’s so hard to tell on the boxer motors ..even if you drain the block water still in the lines above head leaks in cylinders ....one cylinder seemed for sure leaking ...so after seeing all this with the goo gaskets ...the ones I got started really looking a lot better to me ...and I made the decision to use them just like they were ...fire ring seemed bigger and the overall gasket was just more consistent in make up ...the one thing I did different was I tossed the restrictor plate...and motor has no thermostat at all now ....

I’m thinking seriously of adding more cooling capacity ...seems 1800s have two radiators ..and I’m thinking of gettin a new aluminum radiator you can get right now for oldwings ..and maybe adding more cooling maybe ...just thoughts ...I’m rather sure if I. Mess around with it will push water out. ...I didn’t even think about going there on the test ride ...

 

[dan filipi]

Beyond the fire ring, the gasket is just sealing in coolant and oil.
Why not seal the gasket so coolant can’t get into it in the first place. Copper Coat and Aviation cement come to mind.

 

[joedrum]

Okay went for ride today after running it for about thirty minutes at idle ..then checking for signs of cracked head or failed gasket ...after cool down ..then added about 5ft of overflow tube from expansion tank ...routed it above tank up high at triple tree so if it over flowed I’d see it and went for 50 mile ride .....bike ran cool ...got on it twice first time not so hard ..but enough bounce bike hard frame wrenching power ...then rode my usual path I take nothing from over flow ...bike ran cool in temp ...then later closer to the house on the way back ...I really got on it ...hard in first gear hit second hard also bike was flying pass 70 mph on the speedo ...hit it hard in third but just for second cause traffic was coming ...my usual hard hit I can do safely 90plus mph....if it was going to spit out it should have ...went about 5 miles to home ..bike ran cool and wasn’t hot ....small victory so far ...

 

[Ansimp]

:good:

 

[desertrefugee]

Fingers crossed for you Joe. I know I'm always nervous that first couple hundred miles after doing head gaskets. Sounds like you nailed it!

 

[DaveKamp]

Sounds like a good result so far. Double-check the head bolt torque.

Show us the photos of the head and block when you got it apart, and the gaskets on both sides- I wanna see where the combustion gases were pushing through.

 

[joedrum]

I just used one gasket on the head ...these gaskets were different than the goo gaskets that were tried before ...if you read my post there talk bout the swell in the goo gaskets exposed to the water jackets that was full of water ......anyway no double gaskets used with copper Dave ..

 

[DaveKamp]

But did you take pictures of the head and block mating surfaces and the combustion chambers? They tell you a story...

 

[joedrum]

No I didn’t ...I had to work steady ...it was looking like rain the whole time Dave ...wanted to ...but believe me I know what my eyes were looking at ...I have very smart hands and know what im doing ....my backyard caveman non engineering skills ...beats engineers dam near 100% of the time in all things I do ...not bragging but was very fortunate to be taught by someone who taught me not a certain thing but taught me how to do any dam thing I wanted to even if I never done it ...it was the best education ever ...beats any paper back school period ...there are many pics of these heads in my album on the forum ...truth is I change the head gaskets did some others things to the bike in just a few hrs ...

 

[dan filipi]

"Well bike running ...put two head gasket on"

Did you put 2 head gaskets on the one head or 1 gasket each head? You were talking about sandwiching so I thought I'd ask.

 

[joedrum]

Just one on each head ...the gaskets were so much different than all the others I used ...it was worth it to try them on there own merit ...fixing to test ride it today temps have warmed up ....

 

[dan filipi]

joedrum » 8 minutes ago[/url]":3pjkd7lt]
Just one on each head ...

This thread is 9 pages and all over the place, so I just wanted to ask specifics...
So far with the new head gaskets, has the "Hooch cooling system pushing out water from cap" not done this?

 

[joedrum]

I’ve been on 2 test rides so far ...the only mods donecso far is no thermostat is put in ...and the overflow is about 5ft long and runs above expansion tank and if it pushing water out it should drain back in expansion tank ...it’s been kind of cool here for fla ...but so far things are looking good ...may be switching to some kind as racing coolant mix for maximum heat transfer over antifreeze ..

 

[desertrefugee]

I thought we had discussed the notion that this was not necessarily an overheating condition, but rather an overpressurization condition. I thought that was why the head gaskets were swapped since bubbles were seen in the coolant suggesting combustion gases were getting in.

Maybe I'm missing something, but at this point, I'm getting confused as to what the actual problem was (other than the thread title itself) and the progression that lead to the remedial steps that have been taken.

Empirically measuring the coolant temperature was suggested, and I would think that that should be a first step before concluding but you have a coolant system deficiency. Otherwise, you're going through this huge ceremony for essentially nothing.

 

[joedrum]

Well ...one thing for sure the head gaskets bought were completely of different make up than stock Honda gaskets or the clone goo gaskets ...when I took bike apart ..there were signs of compromise head gaskets ...the fact that the goo gaskets swell and had water in the middle of them means to me very inferior product ..so trying the new gaskets not made that way was a complete change ...I’m betting there were exhaust gasses getting in coolant ..causing the extra pressure ...and water push out of cap ...also it doesn’t have to be hot for that to happen ...so far with the new gaskets and several hard hits in power and no thermostat there’s been no loss of water and the motor running cool ...today I really hit the throttle hard ...bike is really fast how fast I’m not sure but I’ve look at speedo shots of blower powered oldwings ...it seems to match those mph swiftness maybe quicker ...I’ve ran about 4 gallons of gas trough the bike since work was done ....a lot of he posts here were not me telling facts but just talking about what might be going on ....the whole point of the thread to get opinions and talk what might be tried ....

 

[desertrefugee]

Sounds to me like you're at the point now where you just have to ride it see if the head gaskets solve the problem

 

[ekvh]

I jumped into this conversation to learn. Having very similar bikes, I had the same issues with mine and assumed it was head gaskets. I know the first time mine became a head gasket from running too low on coolant, so I changed to copper. When it started overflowing the reservoir with the copper I looked elsewhere. First I found a bent radiator cap surface on the radiator side. Fixed that, problem persisted. I ran it more, but got pretty nervous about scalding water spewing on my leg. So I pulled heads, examined gaskets and couldn’t find a leak point that was obvious. I couldn’t smell exhaust in the coolant. I tried the dye which shows exhaust leaking into the coolant. It was negative. I decided to increase the size of the reservoir. I now see surges of coolant out of the cap through clear tubing into the reservoir. In the morning or after it cools off, I see coolant in the tube being sucked back into the radiator as it should. Sometimes it’s empty in the tubing, sometimes it’s not.

Most figured it was my copper gaskets with aircraft sealant. I am not so sure. Once my reservoir was large enough I haven’t had problems. I have had the heads off and on 3-4 times on the first set of copper, once on the second set which was too thin, and twice on the current set. I will post pics of my gaskets for anyone who thinks they have been leaking. Maybe trained or experienced eyes will see something I don’t.

I’ve been trying to read up on pump cavitation, and it is pretty much above my pay grade. One interesting note was that automotive pumps have been showing signs of cavitation with the advent of turbochargers and the increased rpm. The article stated the problems occur at 7-8000 rpm. Those are the rpm where mine would spew. The stock 1000 early models redlined above that and I don’t recall anyone having trouble with them.

Maybe Dave can enlighten us on what pump cavitation effects could have on this. Eventually we should see wear on the impeller or passageways, but I’m thinking that would take a while.

Would cavitation at the pump stop flow enough to create a surge at the top of the radiator? The coolant is circulating at a decent speed. It can’t stop on a dime, there would be some ramming effect. Could it be enough to pop the pressure cap?

Wouldn’t a compression leak result in air in the system?

 

[mcgovern61]

Would cavitation at the pump stop flow enough to create a surge at the top of the radiator?

Yes. First, it is important to understand, "cavitation". Cavitation happens when the surface area of a blade creates a high and low pressure (just like an airplane wing). When those pressures are created in fluid, the edge of a propeller blade will actually experience small explosions due to the pressure differences. These explosions create small air pockets and actually boil the liquid at the point of cavitation.

Unlike airplane wings or propeller blades, water pumps for these engines are not designed to create either high or low pressure (hence the reason for the flat blade on the impeller). If you spin the pump faster than it can push fluid, you will create a low pressure wave on the back side of the blades which will cause cavitation. The faster it spins, the higher the pressure differential, the greater the explosions.

I deal with this in marine all the time. When we increase the horsepower on any engine, the entire cooling system has to be reviewed. Most often, it is not the increase in horsepower as much as a higher torque curve and almost always higher RPM. Recirculating water pumps are built for a specific range of RPM, pressure and gallons per minute of flow. If any of these exceed the pump's ability to operate correctly, you will lose the pump to cavitation.

If you want to verify cavitation as an issue, drop your coolant, remove the cover of the pump and look for dark spots on the impeller.

 

[DaveKamp]

First off, the photos you posted of your head, block, and gaskets ARE telling you a bit about what's going on in there. Compression leakage has a very convenient path from the top of the cylinder bore, around the gasket, directly into the cooling jacket. Notice how the gasket has rings to match the cylinder wall, then the water jacket, then the block? Now look at the COLOR of the gaps. When there's combustion gas leakage, carbon soot illustrates a path where coolant quenches what's burning, and the result is dark staining, and your gasket and heads show carbon stains.

The GL cylinder wall design comes right up to the head mating surface like it's 'floating' in the middle of nowhere. Really, it's not, BUT.. the top of the cylinder wall is separated from the rest of the block, and hence, the sealing surfaces DO move independantly, and this is VERY intentional... by allowing that cylinder wall to be totally disconnected from the block, it means that the expansion of the top of the cylinder will be uniform in temperature, hence linear in expansion with temperature variation. Irimajiri knew EXACTLY what he was doing with this design... he knew that putting a 'bridge' between the top of the bore and the head would mean that there'd be a 'cold spot' at each bridge, and as a result, the top of the block would be stressed by non-uniform thermal expansion... it would warp, and never seal well... the pistons would wear out-of-round, and it'd lose performance rapidly over time.

Having proper torque is absolutely, positively mandatory for these to seal right. Not too much, and not too little.

As for your question about 'pushing air into the cooling system'... yeah... not air, though- fuel, air, and exhaust gasses. It'd be the same as taking a 200psi air hose, and shoving it into one of radiator hoses... and the end result would be that the pressure cap would blow off the pressure once it exceeded 16psi or so. The other side effect, is that the area where bubbles were 'hanging out' would get rather hot, causing more seal problems.

The giveaway of compression leakage, is that the coolant appears to be boiling, even though it's not above boiling point.

Cavitation, as Gerry noted, is a function of physics. At sea level's atmospheric pressure, water boils at 212F. If you were to place water in a vacuum, crank the pressure down to less than half atmospheric standard, it will boil at a much lower temperature. You can put a glass of water in a vacuum chamber, and make it boil at 55F.

Now imagine a brick, being pulled through the water at some intense velocity. The drag of pulling that brick is high... and that's because it's trying to PUSH water as it's going forward, and PULL water (to fill in behind it). The difference of high frontal and low rear pressure results inwhat's called 'drag', and that space behind the brick is a 'low pressure' zone. Pull it way, way fast, and that pressure BEHIND it gets so low, that it starts water boiling.

Boat propellers cavitate due to generally TWO reasons: 1) Too much horsepower being forced into theflywheel, and 2) nicks, scratches, etc., on the propeller blades causing cavitation to START in the first place.

 

[joedrum]

Hmmmmmm well now Dave ...if the dark rings are a sign of exhaust gases leaking into water jacket ...it’s looking like the problem would be severe as the stain is rather consistent...I’m not sure that possible as Eric says things are iffy about what’s going on ...and it does not explain the clear spots that are present in the water jacket area ....but in the same breath looking at the. Bare head the dark spots on it seem to be where the torque would be greatest around the head bolts ...in general it’s my belief that there is leaking to some degree in Eric’s motor but as it goes with copper gaskets with oldwing set up irs just bad combo ....as for your comments on unsupported cylinders at the top of the block as being good ...I couldn’t disagree more ....as for the comment of warpage and sealing problem ...well the unsupported cylinders are what’s having the problem here ...if this was such a great thing why are there so many motors not done this way ....as far as the heat is concerned ..it’s greatest at the top that’s wear the fire is at ...i general there stress and leverage going on from piston rods and being held at the top would definitely brace this effect way better than floating sleeves by far ... in my opinion ...and regardless of weather this true or not ..the fact that the head gaskets that are made for oldwings degrade in this condition out weighs everything mentioned ...I will post pics of the head gaskets that came off my bike ..the whole idea they swell up proves it’s an inferior product in this set up ...one thing the copper shows it doesn’t degrade at all

As far as cavitation goes ...water no different than air flow ...if the drag gets big enough behind blade that it runs into the next blade there’s no feed to it rather plain and simple ..but all this would decrease flow ...so I’m thinking it’s a non issue except for one thing ..if you stayed there the motor would get hot ...

Long story short ..the whole idea the head gaskets swell To thicker than what they were made says it all ...and is the problem here ...in a motor set up like these oldwing motors are ..a oring seal made of copper or steel that cut into head head and block is the only thing that would seal this set up right in my opinion ...you wouldn’t need anything else going across the water jacket at all just gasket where the head bolts are at ..in my opinion ...