Hi everyone. I am having more problems with my recently rebuilt (15 hrs ago) 1990 175 hp 4.3l mercruiser with Alpha 1. I am throwing in everything I observed even though I would think some of the "issues are not related. Here is the summary:
1) Boat worked flawless until last weekend. The raw water feed line came off drive and I overheated the motor. Took it to merc shop and they indicated it appeared to be a minor overheat and they have seen much worse without issue. Replaced shutters and both rubber exhaust pipes. The shutters were melted badly. The rubber exhausts really wasn't that bad and everything else was unaffected. Also replaced the raw water feed line. They brought it up to temp on muffs and everything seemed fine. I asked if we should compression test - they told me to try it first restating how minor the over heating damage seemed to be.
2) Just came back from wet test. Motor ran perfectly. Noticed the trim on the motor was not working properly. The trim indicator would not move for first few seconds and would shut off when still between the two lower indicators on the gauge. The trailer switch could still be used to raise the outdrive into the max upper position for transport, but seemed weak near top. Maybe the new raw water feed line is in a different position?
3) Noticed a small sheen on the water the boat when in neutral. The sheen was more noticeable when you throttled the motor a bit. Opened engine compartment and noticed steam coming out of flame arrestor. Enough that the top of the carburetor was damp. Engine was running very smooth but did seem a tad rich. Steam was noticed coming out the valve cover vent lines. Choke confirmed to be open. We were all amazed that the motor could run this well and be displaying symptoms of a bad head gasket.
4) May have heard a very brief squeal when it stalled initially on cold start- almost like a belt squeal from the motor . Very minor but had never heard this before.
5) Engine oil is clean and at normal level.
6) Boat got up on plan easily and ran at 150-170F. We did not go far - 2-3 minutes.
Next Steps:
a) Compression test and leak down test
b) Check Drive oil
c) pull spark plugs and check color
d) Crank seal behind drive belt sheave/ balancer???
Is there anything else I should do tomorrow after I drown my sorrows with wobbly pops tonight? I have done a search on here and it seems like steam may not that big a deal but this seemed excessive. It was foggy/damp out today though. We also had very heavy rain 2 days ago (over 6" in 4 hours) and local flooding. The boat was at the shop, but I believe they had it covered.
1) Boat worked flawless until last weekend. The raw water feed line came off drive and I overheated the motor. Took it to merc shop and they indicated it appeared to be a minor overheat and they have seen much worse without issue. Replaced shutters and both rubber exhaust pipes. The shutters were melted badly. The rubber exhausts really wasn't that bad and everything else was unaffected. Also replaced the raw water feed line. They brought it up to temp on muffs and everything seemed fine. I asked if we should compression test - they told me to try it first restating how minor the over heating damage seemed to be.
2) Just came back from wet test. Motor ran perfectly. Noticed the trim on the motor was not working properly. The trim indicator would not move for first few seconds and would shut off when still between the two lower indicators on the gauge. The trailer switch could still be used to raise the outdrive into the max upper position for transport, but seemed weak near top. Maybe the new raw water feed line is in a different position?
3) Noticed a small sheen on the water the boat when in neutral. The sheen was more noticeable when you throttled the motor a bit. Opened engine compartment and noticed steam coming out of flame arrestor. Enough that the top of the carburetor was damp. Engine was running very smooth but did seem a tad rich. Steam was noticed coming out the valve cover vent lines. Choke confirmed to be open. We were all amazed that the motor could run this well and be displaying symptoms of a bad head gasket.
4) May have heard a very brief squeal when it stalled initially on cold start- almost like a belt squeal from the motor . Very minor but had never heard this before.
5) Engine oil is clean and at normal level.
6) Boat got up on plan easily and ran at 150-170F. We did not go far - 2-3 minutes.
Next Steps:
a) Compression test and leak down test
b) Check Drive oil
c) pull spark plugs and check color
d) Crank seal behind drive belt sheave/ balancer???
Is there anything else I should do tomorrow after I drown my sorrows with wobbly pops tonight? I have done a search on here and it seems like steam may not that big a deal but this seemed excessive. It was foggy/damp out today though. We also had very heavy rain 2 days ago (over 6" in 4 hours) and local flooding. The boat was at the shop, but I believe they had it covered.
