5.7L bravo 1 Water in cylinders 1 and 3 after overheat need advice

[Oshkosh1]

Pull the stbd head. It's warped, the gasket is blown and that's where the water is coming in from. No more testing(I'd have quit after that compression test on the 7th) is necessary. Leakdown tests are nice, but in your case with those low numbers is not needed as nothing you can do short of pulling the head will fix them.

 

[mr300z87]

But the water is on the port side??? Also let me clarify that I did have an over heat situation however the temp never got over 200 degrees. A 5.7L/350 in a car would run normal between 180 and 195 degrees all day long so 200 is not really that hot. I shut it down at 170 then re started it for less that a 15 to 20 seconds when it hit 200 (no load) and set the alarm off I then turned it off immediately. I have since fixed the clogged intake hose put another 6 hours on the engine mostly no wake and 3K RPM cruise speed but I did run it closer to 4K for a few minutes on a couple of outings when the wife was not with me, port side exhaust flapper was still intact. If the weather was better here I would run another compression test with the throttle open to see what I get but its to hot out. Wouldn't an leak down fail if I had a blown head gasket? I am not ruling out a blown head gasket but I do no want to tear it apart for no reason either.

One other thing I noticed that I never saw before is white oily stuff on the breather tubes
port

starboard


Since changing the manifold and elbow it has only run on hose so even though the gauge come up to temp it never really get fully warmed up like it does under load. Is there anything else to check before I pull the heads? BTW at this point the engine still runs strong and smooth so if I could find the water intrusion and finish the season out as is I can address the low compression issue later on. I just want to go boating.

 

[NHGuy]

Don't get too worried about the stuff in the oil lines unless it starts showing int the oil. If you don't get the engine warm that root beer float stuff will be with you.
You still have low compression, worse is on stbdside , but both sides have low psi holes. It won't go away without repair, I'd get the heads off.
I completely understand about the short season, we have that too.

 

[mr300z87]

Going order head gasket set. Is this the correct one https://m.summitracing.com/parts/fel-17214/none/images

 

[wahlejim]

It may not be just the head gasket. You will have to get the heads checked to make sure they are not warped. A machine shop will be able to check it for you and fix if necessary. If the heads are warped, you will just be throwing money at gaskets without fixing the actual cause.

 

[thumpar]

Not just checked for warping but cracking also. He the intake checked for the same.

 

[vetting]

I have a 5.7 alpha 1 and had a similar situation last year. Mine ended up being cold water that came up through the exhaust and cracked the head. When you are running it on the hose, its not the same amount of water flowing through as when you running it on the lake. Less water flow and less operation temp would equate to not getting the same expansion/contraction of warp/crack/or gasket issue.

 

[harleyman1975]

Also you guys who boat in the brine can have the heads and/or intakes rust through. Heads have been seen to rust through under the valve seat. Pressurizing the cooling system would elude to this or just pull the heads and have machine shop check them and intake manifold.

 

[camalot]

Also you guys who boat in the brine can have the heads and/or intakes rust through. Heads have been seen to rust through under the valve seat. Pressurizing the cooling system would elude to this or just pull the heads and have machine shop check them and intake manifold.

Second that one........not uncommon for the heads to corrode through in the inlet or exhaust duct. Comp test and leak down won't pick that up.

 

[mr300z87]

My plan right now is to pull it apart, and get the heads check out. Was also thinking before dis assembly doing another comp check and leak down on all 8 just for a baseline. My issue here is time and $$$s. If I take it apart and find that I need a total rebuild or new heads this would put me out for the rest of the season. I have another project, see project Sea Ray in my signature file, and would change direction to try to get that finished for next season. Which by the way is the plan for next season anyway. Then work on this when time permits but I do not want to leave the engine open to the elements for long periods of time. This is why I want to do as much troubleshooting before dis assembly starts.
I fully understands what you guys are saying about running in the water under load is different then the hose and I stated that in my last post. My biggest issue here is that I did not overheat this thing hot enough to do any real damage and I have owed this engine for 5 years and put close to 100 trouble free hours on it. Also the fact that I can not definitively diagnose the issue is driving me nut. BTW the engine runs great and has plenty of power to push my 20 ft cuddy with 6 adults on it. Will keep posting here as I move forward.

 

[thumpar]

Just because the gauge read 200 doesn't mean that is what was going on at all points of the engine. That is only from the sensor. 200 is really high BTW. The head could have been 900 around the exhaust without water.

I had a 4.3l that started making milk shake. There was never an overheat and it still ran great. It turned out the be the intake gasket. Sometimes things just happen. At this point I would just pull it apart. Maybe setup video so you can see the parts as the are taken off one by one. You may find something obvious.

 

[mr300z87]

Tonight some friends came over to kick my butt into gear. We pulled no 1 and no 3 plugs and found water on no 1 plug so I cranked the engine a bit to clear any water before we continued. Next I pulled the elbow off and found standing water in the exhaust but did not find evidence of a gasket failure. These were new merc manifold and hge elbow, with merc gasket. We were running out of daylight so no photos yet. Found some milk shaking under the valve cover also but still no sign of water in the oil?? The last thing I did was remove the ps pump in preparation to remove the intake and port side head. Just being lazy and cheap, but can the intake be removed and replaced with carb and thermostat housing still on? My plan is to replace both head gaskets but at this time my focus will be on the port (water intrusion) side to evaluate. Depending on what I find will determine whether to try and fix her and finish out 2016 or move on to the Sea Ray. I can except the loss of a month of boating knowing the Sea Ray will be ready for 2017.

In the end I may just decide to part the Invader out which is too bad because it is a really nice clean old boat but holds little to no value to anyone but me. I know it has a solid working B1 drive that I could bolt onto the Sea Ray tomorrow as well as a lot of good parts including a trailer. She is worth more in pieces then whole with no engine. But the other side of me says it is not my style to just destroy something that is almost 30 years old and is so well preserved. Besides when the Sea Ray is done I will need some kind of project to keep me out of trouble. Sorry for my babble as I am sure some of you guys understand my problem here. Tomorrow will be here soon enough is I will know more. As one of my favorite musicians once sang "there's nothing left to do but smile smile smile". Photos of my finding tomorrow. Have a great night.

 

[mr300z87]

Just thought of another question that popped into my head, I have a friend who is replacing the Vortec 350 in his pickup with a hot rodded big inline 6, not sure I understand that, but never the less, he said I could have the runnin 350. Did Merc ever make a 4 barrel intake for the Vortec heads? If so what else would be Vortec specific that would be needed to covert it to marine use. I would want to use as much stuff from my original set up as possible. ie: carb, TB4 ignition, Rochester 4barrel and accessory brackets. This could be an inexpensive way to put her back together plus a few hp too. If it comes to engine replacement.

 

[bruceb58]

Is the pickup 96 through 98?

http://www.michiganmotorz.com/vortec...ent-p-465.html

 

[mr300z87]

Thanks Bruce, that would be the intake needed I think. I do not know much about the engine other that he said it was a Vortec. The truck is from the late 80s I think and this is the engine that it had when my friend bought it. Why anybody would go backwards and replace a 300 hp v8 with an antiquated in line 6 is beyond me. But a free running engine when one is needed is never a bad thing.

 

[bruceb58]

You better check the intake manifold bolts. They didn't come out with the true Vortec heads until 1996. GM called some engines Vortec before that but they aren't engines with the true Vortec heads.

Pre Vortec had 12 bolts...Vortec had 8.

 

[mr300z87]

Thanks again Bruce for the Vortec info. That engine is still a ways out but if and when I will make sure I get all the right stuff. So tonight my friend an I did the port side head removal, and we took these photos of what was found. First on the under side of the valve cover there was some rust but it looks old.

We found some milk shake in the rockers and cylinder head also

I then pulled the distributor but did not photo but it had some mike shake also.
next was the intake where there was more

and finally the port side head. These are the no 1 and 3 that have had water in them.

this is a photo no 1 and 3 valves


All in all the cylinder look OK no scoring or major issues, but we were running out day light so it was tough to say for sure. Tomorrow when I get home from work I am going to pull the head out and have a really good look at it, will try checking for flatness but will most likely bring it to a machine shop to have is checked out. I did not see any definitive signs of a blown gasket but it looks like if could have leaked by the water jacket near the intake between 1 and 3. I also need to get the oil out of this thing as even though I show no signs of water in the oil I am sure it contaminated. I'll get some brighter photos tomorrow. Please let me know what you all think, should I try and bolt this thing back together with new or repaired head? Of course I will do the starboard side also but just wanted to get water out of the port side and see if there was any damage to the cylinder or pistons first before I go any further.

 

[Grub54891]

Well, that's defiantly water in the oil. When you remove the oil, put some in a clear jar and take a pic. I know just checking the dipstick don't always give you a clear look at the oil/water mix. the jar test tells you a lot more. I bet if you did that before it would have showed you earlier on. In any case, I hope you find the leak, and it's a simple one to repair. I'd be scrutinizing the bearings at this point as the were lubed with the water mix for awhile also.

 

[mr300z87]

I am sure the oil is contaminated with water but it is still clear, I would have thought I would have gotten mike shake there too by now. What is driving me nuts and keeping me awake at night is not finding any clear signs of where its coming from. Hopefully inspection in the day light will reveal something the afternoon.

Mike

 

[mr300z87]

Last night when I got home from work and still has good daylight I went out to give the head and intake manifold a good inspection. What I found was nothing really. neither water jackets look too bad, I see no signs of leakage into the exhaust port but I can see that there was water in the exhaust port at one time though. Does this lead back to the exhaust? Do the elbows fail?
One last note in the same area on the gasket I mentioned above between the gasket and the head was some king of moisture. This could be a gasket failing around the water jacket. After my hands were nice and dirty our power went out so I could not upload the photos I took. So sometime today I will get a couple more photos.

Have a great day