bayboatersf
New Member
The engines survey with compression check for the twin 8.1 Mercruisers will be done in the next couple of days.
What should the compression be?
Thanks
What should the compression be?
Thanks
Ready for engines survey - question
- Thread starter bayboatersf
- Start date
AKBASSKING
Active Member
- Apr 13, 2008
- 4,649
- Boat Info
- 1988 Yacht Fisher
- Engines
- Twin 375hp Cat 3208 T/A
On my 260hp mercs (GM 350cid) it is 150psi "dry"
moparlvr4406
Active Member
- Jun 29, 2011
- 4,462
- Boat Info
- 1985 340DA
1966 SRV180
(2)1960 Sea Ray 600
(2) 1963 808 Cruise-a-bouts
- Engines
- twin 350hp Crusaders 4.0 Onan /
Merc 950 SS
Merc 650
Merc 1100
twin Johnson 40
15% variance from highest to lowest cylinder in each engine
150 is a good general rule but the variation is what to look for....shows individual cylinder wear and potential problems
150 is a good general rule but the variation is what to look for....shows individual cylinder wear and potential problems
my3sons
Well-Known Member
- Feb 24, 2009
- 3,046
- Boat Info
- 2004 400DB, Onan 9 kw Generator, Highfield RIB,
- Engines
- Cummins 6CTA M-3
when mine were surveyed in 2008, the 16 cylinders ranged between 178 and 193. but as stated above, should be within 15%
good luck with your survey
good luck with your survey
HUMPH
Well-Known Member
- Nov 4, 2009
- 7,618
- Boat Info
- 2003 410DA
2009 Walker Bay 13’
- Engines
- CAT 3126TA's 350HP/
50HP Honda
Who is doing the survey for you?
rcon
New Member
- Jun 16, 2011
- 481
- Boat Info
- Preparation
'93 300 Sundancer
w/ Kohler genset
Raymarine E7D
- Engines
- 4.3l Mercruisers w/Alpha 1
As someone who just purchased after a "survey", make sure you have a full understanding of what exactly they're looking at and what they're not.
I organized our local sea ray dealer to survey the boat and all I ended up with for $1000 + $300 in lift fees was an engine condition report and an insurance check. Whilst I didn't find anything during the week we spent in the yard that would have been a deal breaker, I certainly would have negotiated even further if I was more aware of the condition of some items (specifically the electric winch - I now have a new one as the old one was more than just "not working")
Part of this comes down to my lack of understanding what I was getting for my money. I had hoped that "buying the best" would help protect me from my lack of knowledge but it wasn't to be.
ie, water tight seals? Rot in the coring? Were the two big ones for me that I thought a survey might have picked up on - but again, this was my first purchase and maybe I should have found them myself.
I organized our local sea ray dealer to survey the boat and all I ended up with for $1000 + $300 in lift fees was an engine condition report and an insurance check. Whilst I didn't find anything during the week we spent in the yard that would have been a deal breaker, I certainly would have negotiated even further if I was more aware of the condition of some items (specifically the electric winch - I now have a new one as the old one was more than just "not working")
Part of this comes down to my lack of understanding what I was getting for my money. I had hoped that "buying the best" would help protect me from my lack of knowledge but it wasn't to be.
ie, water tight seals? Rot in the coring? Were the two big ones for me that I thought a survey might have picked up on - but again, this was my first purchase and maybe I should have found them myself.
Last edited:
bayboatersf
New Member
The engines survey was completed today. According to the mechanic who checked all of the engines functions through a computer, everything looks good except for few minor things to be fixed.
The compression check come out very good with compression between 192 and 196 over the entire cylinders.
Now I am just waiting for the oil analysis results.
The compression check come out very good with compression between 192 and 196 over the entire cylinders.
Now I am just waiting for the oil analysis results.
nowakezone
New Member
:wow:
Sorry, I just had to after my recent experience. :grin:
No intention to hijack the thread, but I feel for you rcon. I wasn't impressed with the "survey" topsides for sure. The hull and running gear analysis is great, but making sure everything turns on....well, my kids do that daily.
