980 hours on engines - compression test

[shaw520]

Then I re-plugged that ignition wire and went to the next cylinder's wire unplugging and re-plugging until all cylinders had been run for 2 mins getting the seafoam mix without firing.

Just curious here, but on some EFI systems, when the computer detects a misfire it will **** down that injector,.?? Not sure if this pertains to your system.

Also,.. my UN-professional opinion here is;.. a well maintained marine motor with 1000hrs with no issues needs nothing,... but if you're itching to do 'something',.... better flowing heads while maintaining stock compression would seem most sensible.

Also,... weren't you the guy that converted to a closed cooling system,.. ???? If so, removing the heads is a great opportunity to really flush water jackets ! I have found that most sediment settles at the bottom of the block and can be accessed through the top of the block with the heads off.

 

[tpenfield]

I have the MEFI-1 controllers on the engines, which are the first generation of fuel injection. If does not seem to have the misfire detection as it supports no error codes of such. Based on how the engines behaved as I progressed through the de-carb process, it seemed that the idle cylinder was getting injection.

Based on the comments, I I did a basic inspection of the bottom end (without disassembly), and it seemed good, perhaps I could just do the top end and not look back.

I believe that starboard engine had a valve job already during the boat's life, but the port engine is original.

 

[tpenfield]

As far as modifying the engine, I have no plans to do so, because I intend to sell the boat in the next 3-4 years. So I’d do the engine work next year and then run the boat for 2-3 more years before selling it.

The Admiral and I are considering the Formula 350 SS as our next boat.

 

[Scott Danforth]

twofootitis.......hope you dont get a severe case of it...... my last one was fivefootitis

 

[tpenfield]

twofootitis.......hope you dont get a severe case of it...... my last one was fivefootitis

Well my last case of the 'itis' was ninefootitis . So, if this case be only twofootitis, then I would consider myself to be on the mend.

 

[Mischief Managed]

No inboard or outboards in your next boat? I keep my boat on a trailer and I am still tired of sterndrives; can't imagine keeping it in salt water all the time.

 

[QBhoy]

Can I ask what oil you are using ?
i changed from the standard Quicksilver 25-40 to the synthetic blend quicksilver 2 years ago and change it twice a year. I’ve noticed since doing this the used oil doesn’t smell of washed fuel anymore and the oil pressure is noticeably higher when warm. It used to smell of fuel slightly (not as much as my old carb).
Id imagine a big cause of lost compression is down to fuel washing the bores and thinning oil. Not a huge issue on a mpi generally because the fuel is measured with injection. But used to be a massive deal on the old carb engines. Especially running at low speed sustained.

 

[shaw520]

Can I ask what oil you are using ?
i changed from the standard Quicksilver 25-40 to the synthetic blend quicksilver 2 years ago and change it twice a year. I’ve noticed since doing this the used oil doesn’t smell of washed fuel anymore and the oil pressure is noticeably higher when warm. It used to smell of fuel slightly (not as much as my old carb).
Id imagine a big cause of lost compression is down to fuel washing the bores and thinning oil. Not a huge issue on a mpi generally because the fuel is measured with injection. But used to be a massive deal on the old carb engines. Especially running at low speed sustained.

Maybe thats why some of us old schooler's would use thicker oil as the engine aged,... now a days thats not such a good choice.

The percentage of fuel wash will show in an oil analysis... a good indicator of piston to cyl wear..

 

[shaw520]

Well my last case of the 'itis' was ninefootitis .

Just keep going with ninefootitis

 

[tpenfield]

No inboard or outboards in your next boat? I keep my boat on a trailer and I am still tired of sterndrives; can't imagine keeping it in salt water all the time.

Sterndrive boats just seem to fit our boating style best, lots of stern access. My brother has a Grady-White 305 with twin OB's and we have been on his boat a few times, just didn't think it fit our needs as well.

We have become addicted to Formula, but I'm not sure if any of the large OB models are going to be in my price range The 350 SS comes with 3 outboards, if configured with OB's. Otherwise it is 2 Mercruiser 8.2's with the B3 X.

I have been able to maintain the outdrives in salt water fairly well. A Full closed cooling system is a must. The Formula 350's with the 8.2's seem to have closed cooling :thumb:

Can I ask what oil you are using ?
. . . .

Might be best if I declined to answer But if you must . . . 10W-40 'dino' of no particular brand. Never have to add oil during the season.

 

[Mischief Managed]

Sterndrive boats just seem to fit our boating style best, lots of stern access. My brother has a Grady-White 305 with twin OB's and we have been on his boat a few times, just didn't think it fit our needs as well.

We have become addicted to Formula, but I'm not sure if any of the large OB models are going to be in my price range The 350 SS comes with 3 outboards, if configured with OB's. Otherwise it is 2 Mercruiser 8.2's with the B3 X.

I have been able to maintain the outdrives in salt water fairly well. A Full closed cooling system is a must. The Formula 350's with the 8.2's seem to have closed cooling :thumb:

That 350SS is a gorgeous boat. I can totally understand why you want one. I see quite a few of them (and other size Formula SS boats as well) on Winnipesaukee. They really ooze quality.

I stupidly waited 12 years before I added an ESP to my stern drive boat, and wish I'd done it sooner, so I now REALLY know what you mean about stern access...

Our next boat will be a twin inboard diesel live-aboard with a "fast" (50ish HP RIB) over-sized dinghy. I know I will miss the 35 MPHish cruising speed of my current boat, but I think living on board will mean there's really no hurry to get anywhere 99%+ of the time. The plan is that the live-aboard will spend the majority of time anchored and most exploration will be done in the dinghy.

 

[alldodge]

Can I ask what oil you are using ?
i changed from the standard Quicksilver 25-40 to the synthetic blend quicksilver 2 years ago and change it twice a year. I’ve noticed since doing this the used oil doesn’t smell of washed fuel anymore and the oil pressure is noticeably higher when warm. It used to smell of fuel slightly (not as much as my old carb).
Id imagine a big cause of lost compression is down to fuel washing the bores and thinning oil. Not a huge issue on a mpi generally because the fuel is measured with injection. But used to be a massive deal on the old carb engines. Especially running at low speed sustained.

Smelling fuel in the oil is fuel wash and a huge issue, carb, mpi or tbi. Only motors designed to run that fat are drag race motors, and they get rebuild every couple runs.

Sorry Ted, if I'm getting off your topic

 

[QBhoy]

Smelling fuel in the oil is fuel wash and a huge issue, carb, mpi or tbi. Only motors designed to run that fat are drag race motors, and they get rebuild every couple runs.

Sorry Ted, if I'm getting off your topic

Think that’s what I said, haha.

 

[Lou C]

Honestly if the engines run well, do not burn oil and you want to sell in a few years, then I'd let her be....There are things that can go wrong in a rebuild....and a lot of time can be taken up trying to put things right, so if you were keeping it indefinitely that's one thing but selling in a few....I'd let those engines be....

I too have though through the I/O vs OB questions many times, and I like the cheaper to repair, simpler by far GM marine engines, but the sterndrive access issues and extra maintenance in salt water are wearisome as you get older. If I get a newer boat, more than likely it will be OB because I will not take an I/O with cat converter exhaust and anything newer than I think 08 will have it. Just say no to an exhaust system that could cost 2000-3000 PER SIDE to replace which is regular maintenance here in the salt. That's why I kept the old boat as long as I have......

 

[tpenfield]

Thanks, everyone for the additional comments. I think I would pull the heads for a top-end rebuild, but only do the bottom-end if there appeared to be excessive wear.

Probably won't start this until next year. I still have an extended swim platform (ESP) to add to the boat. At the same time as I do the engines, I can refurbish the bilge and make it look nice and clean.

Meanwhile, I have sketched out a design for a mobile gantry that I would need in order to remove the rear seat assembly (aka engine hatch) and pull the engines.



I would use 2x6 dimensional lumber for the uprights and a 2x8 for the cross bar, along with some 2x4's for the stiffeners/supports. I'd have to move the gantry about 6 feet back and forth to lower the engines to the ground/stands. (the boat will be on blocks and considered the 'immovable object' )

 

[Bondo]

Meanwhile, I have sketched out a design for a mobile gantry that I would need in order to remove the rear seat assembly (aka engine hatch) and pull the engines.

Ayuh,....... Hi Ted,...... When I can't move a hull to a shop crane,......

I commandeer a backhoe,.......

 

[Scott Danforth]

Check craigslist foe an a-frame gantry. Many in the $300 range. Use it, then sell it for what you paid

 

[harringtondav]

Meanwhile, I have sketched out a design for a mobile gantry that I would need in order to remove the rear seat assembly (aka engine hatch) and pull the engines

FYI, I just ran your lumber BOM thru Menards. $75. Six 300# 4" wheel rigid casters @ Harbor Freight $36. If you don't own a chain hoist, HF has a 1 ton, 10' lift model for $60. Just a $$ reference against hiring a boom wrecker, etc. If you screw your hoist together you'll have some nice dimensional for...whatever.

Maybe also remeasure your engine height, plus sling, plus stern clearance height. Then the drop distance to your cart, truck or stand. I pulled my 4.3 and my bud's 350 and barely cleared both our sterns, and barely got the hook loose on a floor mounted cart. (built on an $11 HF 4 wheel 1000# dolly). I bought a HF lever hoist for versatility on other uses, but was almost chain travel limited.

Modulus E is elusive for lumber. Eyeballing that 1000# mid span looks close. A second 2x8x12 = $9.34

BTW. Nice 3D design program. Was this an at-work "government job" or are you lucky enough to have the program on your PC?

 

[tpenfield]

As far as the design software goes, I have 'Sketchup' on my Mac and it seems to do great for stuff like this.

 

[tpenfield]

FYI, I just ran your lumber BOM thru Menards. $75. Six 300# 4" wheel rigid casters @ Harbor Freight $36. If you don't own a chain hoist, HF has a 1 ton, 10' lift model for $60. Just a $$ reference against hiring a boom wrecker, etc. If you screw your hoist together you'll have some nice dimensional for...whatever.

Maybe also remeasure your engine height, plus sling, plus stern clearance height. Then the drop distance to your cart, truck or stand. I pulled my 4.3 and my bud's 350 and barely cleared both our sterns, and barely got the hook loose on a floor mounted cart. (built on an $11 HF 4 wheel 1000# dolly). I bought a HF lever hoist for versatility on other uses, but was almost chain travel limited.

Modulus E is elusive for lumber. Eyeballing that 1000# mid span looks close. A second 2x8x12 = $9.34

Yes, I figure the design will be fairly economical to build. When the boat is 'on the hard' the top of the swim platform is about shoulder level ( 5' ish) and then there is another 8" (+/-) up to the opening of the engine well. So, the engines will have to clear about 6' in height. Allowing 3 ft of engine and chain hoist, plus the gantry beam puts the top of the gantry at about 10'.

As far as the strength of the gantry design itself, it has been a while since I have calculated sheer force and bending moments, and the qualities of wood tend to vary a bit as opposed to other materials. I was able to Google some stats on a typical 2x8 and the sheer force is a little under 2,000 lbs. The bending would be based on the span, and the cross braces help in that regard, effectively reducing the span. I may go to a 2x10 just to have a bit more strength, while trying to keep the overall weight of the gantry down.

Scott Danforth - I have done some Craigslist searches in the area. It looks like there are some steel gantries for about $1K, which would be a little pricey, but worth a continued look over the winter. :thumb: