Hello all,
I need some input, bought a very well cared for 2000 Regal 2760 w twin 4.3 EFI motors, 650 hours all river water usage on original un molested raw water cooled engines, so after 5-6 hours of run time after my purchase I checked the staroard engine and there was of course a lovely milkshake and aprox 1/2 a quart of extra fluid , this was extremely disappointing, mainly because we have been in boat hell this summer, with several boats.
Now I would typically run to head gaskets, but I hear the 4.3 is known for sometimes blowing the intake gasket at the cross over ports, so we changed that out, ran boat twice for 30 min at idle at the dockand then changed oil, last time oil looked great.
Sunday took boat out with my buddy for an 7-8 mile power run, boat ran great, planed easily and ran its normal top speed, RPM, held its normal cruise speed, etc. returned to dock pretty happy until I pulled the dipstick, more milkshake and definitely way to much fluid in the engine probably a quart extra, also noticed there was milk shake on top of the intake manifold, then took off the spark arrestor off and noticed that milkshake was being blown out of the breather hose and some was actually going into the TB. I then did a compression check, one side all cylinders had 150 PSI, the other side was 145-135-140.
So went and ordered new head, intake and exhaust gaskets and figured it was time to do head gaskets. So I stopped today to pick up the gaskets and in my order was a set of riser gaskets, I told the guy that I did not need the riser gaskets as mine were 1 piece, he then said that there was a very high chance that my whole problem was with getting water in my engine as the 1 piece design has been found to fail quite often, and these are 18 years old.
Now having just spent 4k on 2 exhaust manifolds on the x45 ski boat I didn't need to hear this news, so I went to the boat rigged up a fitting to pressure test to test the cooling system, I could only get 8psi in as going to 10psi would pop the test plug, let sit for 20 minutes sprayed soapy water over all hoses and tester and had no signs of air leakage, in 20 minutes gauge did drop slightly down to 7psi but this could be 19 year old hose expansion, or a slight leak in my test set up, but it definitely had no major leak. My mechanic friend stopped to help, took my air compressor and put 15 psi in a few cylinders, all we had was the gauge on the compressor and it off course dropped a little over a few minutes time but at a rate that was consistent with normal ring blow by and drop was very small and we could not hear any air, or even see any when holding a rubber glove over every port, my mechanic friend said to him the problem is not internal based off our snort initial testing .
So boat showed little or no signs at idle with over an hour of run time at the dock, but got severe with power pass, however higher pressures, load and heat could surely elevate any leaks so????
So I am back to these exhaust manifolds, is there any way to test them? typically I would make plates and block off passages, but with the one piece design I am not sure how to block the oval outlet? May try a plumbing test ball but doubt it will hold in an oval, I would love to test and see if this is the problem to salvage our long weekend then replace during off season for peace of mind, but I also want to make sure it still isn't a head gasket which I could change in 2 hours since I already have the EX manifolds pulled off, so question is do I pull apart a motor that is possibly just fine, just to find its the EX manifold, or do I waste the best weekend of the year, drop a grand and get new EX manifolds and then still may end up pulling it all back apart??
Also I am seriously considering buying newer 2 pc risers, but I am nw trying to find reviews on what brand conversion to buy, and also if dry joint is worth it and if so what kit so I don't have to change the y pipe?
I sincerely appreciate any input in advance!
I need some input, bought a very well cared for 2000 Regal 2760 w twin 4.3 EFI motors, 650 hours all river water usage on original un molested raw water cooled engines, so after 5-6 hours of run time after my purchase I checked the staroard engine and there was of course a lovely milkshake and aprox 1/2 a quart of extra fluid , this was extremely disappointing, mainly because we have been in boat hell this summer, with several boats.
Now I would typically run to head gaskets, but I hear the 4.3 is known for sometimes blowing the intake gasket at the cross over ports, so we changed that out, ran boat twice for 30 min at idle at the dockand then changed oil, last time oil looked great.
Sunday took boat out with my buddy for an 7-8 mile power run, boat ran great, planed easily and ran its normal top speed, RPM, held its normal cruise speed, etc. returned to dock pretty happy until I pulled the dipstick, more milkshake and definitely way to much fluid in the engine probably a quart extra, also noticed there was milk shake on top of the intake manifold, then took off the spark arrestor off and noticed that milkshake was being blown out of the breather hose and some was actually going into the TB. I then did a compression check, one side all cylinders had 150 PSI, the other side was 145-135-140.
So went and ordered new head, intake and exhaust gaskets and figured it was time to do head gaskets. So I stopped today to pick up the gaskets and in my order was a set of riser gaskets, I told the guy that I did not need the riser gaskets as mine were 1 piece, he then said that there was a very high chance that my whole problem was with getting water in my engine as the 1 piece design has been found to fail quite often, and these are 18 years old.
Now having just spent 4k on 2 exhaust manifolds on the x45 ski boat I didn't need to hear this news, so I went to the boat rigged up a fitting to pressure test to test the cooling system, I could only get 8psi in as going to 10psi would pop the test plug, let sit for 20 minutes sprayed soapy water over all hoses and tester and had no signs of air leakage, in 20 minutes gauge did drop slightly down to 7psi but this could be 19 year old hose expansion, or a slight leak in my test set up, but it definitely had no major leak. My mechanic friend stopped to help, took my air compressor and put 15 psi in a few cylinders, all we had was the gauge on the compressor and it off course dropped a little over a few minutes time but at a rate that was consistent with normal ring blow by and drop was very small and we could not hear any air, or even see any when holding a rubber glove over every port, my mechanic friend said to him the problem is not internal based off our snort initial testing .
So boat showed little or no signs at idle with over an hour of run time at the dock, but got severe with power pass, however higher pressures, load and heat could surely elevate any leaks so????
So I am back to these exhaust manifolds, is there any way to test them? typically I would make plates and block off passages, but with the one piece design I am not sure how to block the oval outlet? May try a plumbing test ball but doubt it will hold in an oval, I would love to test and see if this is the problem to salvage our long weekend then replace during off season for peace of mind, but I also want to make sure it still isn't a head gasket which I could change in 2 hours since I already have the EX manifolds pulled off, so question is do I pull apart a motor that is possibly just fine, just to find its the EX manifold, or do I waste the best weekend of the year, drop a grand and get new EX manifolds and then still may end up pulling it all back apart??
Also I am seriously considering buying newer 2 pc risers, but I am nw trying to find reviews on what brand conversion to buy, and also if dry joint is worth it and if so what kit so I don't have to change the y pipe?
I sincerely appreciate any input in advance!
