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Antifreeze in 5 cylinders

V

vikingtime

Contributing Member
1986 454

I went to turn over the engines for the first time this season. The port side started up good. The starboard was hydro-locked with antifreeze in five cylinders. There was lots of antifreeze.

The starboard ran fine when I winterized it in the fall.

I pulled both heads last night thinking it was head gaskets but the gaskets looked good. I'm sending the heads out for testing today.

I did do lots of work on BOTH engines this spring and now I'm starting to think I must have caused this problem.

Elbows/Risers
Boiled HEX
New U coolers
New Raw water pump
All new hoses
New Thermostat
New plugs

When I replaced the risers and elbows - I used the gasket diagram recommended on this site and it appears that I followed it (I can see the tabs of the gaskets -they look correct). I'm wondering if I could have put the "water outlet adapters" p/n 97295 -that go between the manifolds and risers on backwards?

I added 4 gallons of antifreeze to the motor and before I even cranked it, the antifreeze seemed to have drained into the cylinders.

I'm baffled and hoping you can offer some advice.

Thanks!

Scott
 
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Since 5 cylinders were affected, that implies both sides of the V8 are involved. Pretty clearly, the coolant entered either the exhaust or intake valves. When you removed the intake manifold to get the heads off, was there coolant in the intake passages? If the intake is/was dry, then it does point to a major gasket failure on the riser/exhaust side. None of the work you list could cause this issue, except for the elbow/riser replace.
 
Thanks DD,

Yes the intake was dry. I'm going to pull out the manifold/riser/elbow assembly as-is, stand it up and fill it with water - hopefully the water will drain into the manifold and I'll know it's a gasket, water adapter, etc...problem related to the recent work.

Does that make sense?
 
Yes. It might have saved you a bit of work to pressure test the entire cooling system, spark plugs out, with a radiator type pressure tester. Then, just loosen the exhaust manifold to slip it away from the head, check for water there.

Did those "donuts/water adapters" have a nice, smooth sealing surface?
 
I'll bet you neglected to drain the block before unbolting the manifolds! That'll do it everytime.

Jeff
 
My local marine mechanic said the same thing about not draining the block and you're both correct that I neglected to do that but I think it can be dismissed as the source of the problem.

After I completed the risers, but before I refilled the HEX, I changed the spark plugs. There was no antifreeze that came from any of the cylinders. So I think I can rule that out. The problem was after I refilled the HEX (it took 4 gallons btw).

Getting back to the manifolds/gaskets as being the problem; I stood up the manifolds today, filled them with water and after 2 hours they were still holding water...I left them for the night and will check them again tomorrow afternoon. I'll also be having them pressure tested either way.

I continue to be baffled and welcome any input or advice. Thanks.
 
With an undrained system, if you disturbed the riser/donut joint(s) with the exh. manifolds still bolted to the heads, then I can see a likelyhood of coolant entering the exhaust ports. Coolant will run into the gas chamber and then into the head ports. Some exh valves will be closed, so the cylinder won't immediately get coolant, until you crank.
 
The engine wouldn't crank at all, not one bit. Prior to finding out it was hydro-locked, I actually replaced the starter because I thought that was the problem.
 
..."After I completed the risers, but before I refilled the HEX, I changed the spark plugs. There was no antifreeze that came from any of the cylinders. "

Did you spin the motor over with the plugs out to determine this? If not, the plugs would all be dry when removed.

Jeff
 
Sandblasting those donuts may have roughened up the surface enough to provide a leak path, especially if the gaskets were installed dry.

if the heads check out as serviceable, I'd check to make sure you didn't bend a rod and tear up the ring gear, and then put it back together again. Leave the plugs out and fill just the exhaust manifolds with water. If the water comes out of the plug holes, you have an issue with the exhaust system on that side. Once resolved, you can drain the water and then hook up the hoses and fill the HX. Pressure test and if stable, spin it over. If still dry, put the plugs in.
 
fastjeff said:
..."After I completed the risers, but before I refilled the HEX, I changed the spark plugs. There was no antifreeze that came from any of the cylinders. "

Did you spin the motor over with the plugs out to determine this? If not, the plugs would all be dry when removed.

Jeff
Click to expand...
Not sure I understand your logic -maybe I'm missing something.

If the engine was not turned prior or after the plug change, then it had no effect on the antifreeze. What am I missing?

Thanks...
 
I think what he means is the antifreeze would be in the bottom of the cylinder and the spark plug is in the top. Just like if you open a pop bottle the bottle is full but no liquid comes out the top.
 
I pressure tested the manifold using a water hose. It started leaking down with high pressure (est. 50-60lbs). I'm not fully convinced that the manifold is bad since it could be the gasket b/w the donut and the manifold ( all the water was dropping into the exhaust hole closest to the donut. Pro who did th e test was concerned most with the hissing sound when he first set it up the test - said he never heard that when he's done these tests. Either way I'm going to replace the manifold/donut and change the gaskets.

I was told to use Crusader gaskets and not the OSCO (Cru's are much thicker/durable). I also was told to buy Crusader manifolds not OSCO by two different pro's who have both seen casting issues with OSCO.

Waiting for results of pressure test on the heads today. Assuming heads test ok (which I'm hearing is very likely), I plan to remount them and the intake manifold and then pressurize the water system and see if I can locate any issues.

I really wish and hope it was the old antifreeze that dropped in when I changed the risers, etc...but it does not seem likely since the engine never turned and plugs were changed prior to refilling with A/F. I had multiple discussions with some pros on this. They both think that I would have at least seen something when I pulled those plugs.

I should add that I totally screwed up by not checking that engine in the fall when I winterized it to make sure anti-freeze was in the HEX and tested for protection - so I can't say 100% for sure if there was even any Anti-freeze in the engine. I never saw more than 175 degrees - but who knows if my gauge was accurate. It was also strange that when I changed the thermostat as part of my spring overhaul, the thermo was dropped down into the bottom housing instead of the top housing like the other engine - a cover up from the previous owner?

Starting to worry that I cracked the block...but pro's say it's unlikely.

Thanks for the continued input!
 
I'll say one more thing. When I replaced my 30 year old exhaust manifolds, I saw that the "newer" version of the log manifolds include a rear, high tap for the 1 1/4" hose. With that manifold, you don't need the donuts at all. It will move the riser/elbow an 1 1/2" or so forward, but you otherwise won't miss the donut and its additional seal, and long bolt system. I've been running mine for many years this way.
Last item; I use ultra-copper RTV, as thin as possible, on both sides of each fiber gasket. It works.
 
I picked up the new style manifolds (no donuts). When I thread in the 1" NPT elbows should I use teflon tape? Also, I see the Crusader OEM elbows are $40, while the OSCO are $13...trying to decide if it's worth the extra $$ for OEM; I think I would see if the OSCO's are leaking, etc... and they are easily accessed if I have a problem.
 
vikingtime said:
I picked up the new style manifolds (no donuts). When I thread in the 1" NPT elbows should I use teflon tape? Also, I see the Crusader OEM elbows are $40, while the OSCO are $13...trying to decide if it's worth the extra $$ for OEM; I think I would see if the OSCO's are leaking, etc... and they are easily accessed if I have a problem.
Click to expand...

Tape is ok. Better is PST. The Osco bronze fittings are fine.
 
I thought I'd close this thread out with the results.

Replaced head gaskets, intake manifold gaskets and installed new style exhaust manifolds. Ran a pressure test and found no evidence of a leak.

Engine is now running strong. We're still not sure what the source of the A/F was. The intake manifold gasket was in very bad shape and two ports had evidence of water leaks (the "real bad" port was on the "good" side of the engine - meaning only 1 cylinder had A/F on that side) so I'm not convinced that was the root cause.

I am leaning toward the source of the A/F being that I didn't drain the manifold prior to changing the risers (many of you pointed this out). I still don't know why I wouldn't have seen at least some evidence when I changed all the plugs, and I remain confident that the engine never spun to open the cylinders. Hopefully it will remain a mystery and the problem will not reoccur.

Thanks to everyone for all the help!
 
Just a tip for next time...when you winterize the engines, drain all the coolant. Hang a big tag on the top of the engines and one on the dash that say NO COOLANT, TAPS OPEN. Drain the raw water as much as you can. In the spring when you go to fool with the boat there will be those tags to remind you to bust out the Dex Cool. You should also have a maintenance log on board and note what you did when along with the next scheduled interval.
You have certainly gained some expertise in coolant and manifold management at a high price.
 
Some background -

After assembly and before running the engine, we did a pressure test and the water system held 20 pounds for about 10 to 15 minutes.

The saga continues....

Took the boat out for a test run Saturday.

TEMP:

Pumping very good amount of raw water.

The starboard engine is running warm went to 180 quickly before I dropped back on power (port was at 165 - starbrd has always stayed at 165 until late last year - this is what prompted me to do risers, etc...). Topped off antifreeze ran engine for about 10 minutes, let it cool overnight and checked it 24 hours later (yesterday)---A/F down a good one to two inches in hex.

Oil Pressure
Oil pressure was low at about 25lbs at 3200 cruise. Spoke to pro who told me to dump the 10-40 oil and run straight 30 in the 454 crusaders. Changed oil and filter (for 3rd time) and pressure definitely jumped to above 40 at idle (similar to port engine). I did not run the boat out.

Action items:
Planning to check A/F again today (since engine has not been started in two days) - trying to determine if I lose A/F even if when engine does not run.

I will then pull the spark plugs and see if any A/F is present in cylinders. Also will pull thermostat (which was new) and make sure it is a 160. May test run boat without thermostat.

Friend is bringing thermo gun along with mechanical temp and oil gauges to see if boat temp gauge is accurate.

Baffled and frustrated.
 
did you use the "purge plug" at the t-stat housing when you refilled the HX?

If not, the closed side still has air and the drop in coolant level is expected. read the refill procedure in the manual if you have any doubts.

A pressure tester can verify the integrity of the closed side and may be much quicker than pulling a eight plugs.
 
I didn't use the purge plug, but I did top off the A/F once before after running the engine to temp in the slip (assuming 165 was temp) Last time it took 1/2 a gallon. I also forgot to mention I tested the protection of the A/F and it was about -145. I will pressure test again as you suggested and then top it off (with straight water) before taking another test run. Thanks!
 
time for a new hydrometer if you are using ethylene glycol as the -145 deg F is impossible. Min freezing point (lowest temp) is usually around 70% EG to 30% H2O. That concentration is not the best for heat transfer.
 
I was using Prestone extended life concentrate and trying to stay at 50/50 by mixing it with water but as I topped things off I was using straight concentrate.
 
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