1986 PS-190 Advice Please

[Zs86PS-190]

*Sorry for the LONG 1st post-
Hello guys and thank you all for the great information posted in these forums. I am the new owner of a 1986 Mastercraft Pro Skier 190 black/gray with Ford 351w PCM engine. I procured the boat and MC trailer EXTREAMLY cheap due to a divorce situation. I got the boat in late August after it sat for a couple of years. First thing to sort out was it would not run. Found points grounding in distributer and resistor for distributor shot. Engine w/just less than 700 hours fired up and ran very good. Water leaking from both exhaust manifolds. Cracks in the undersides of both. Epoxied manifolds installed new wet exhaust hoses. Splashed boat for the first time the next weekend. Water leak at the drive shaft log & both glass packs. Engine ran hot. Found water pump impeller stripped off the shaft, intact but no water circulating. Couple weeks of work including replacing pump impeller new 160’ t-stat and glassing in drive shaft log & glass packs. All good, or so I though. Splashed boat again ran nice & cool with no leaking. Went to put the boat on the trailer and engine stalled like out of gas. Could only idle in. Turns out that with good water circulation or should I say too good of water circulation found engine oil pan full of lake water and engine will not turn over freely. Damn. Pulled plugs drained oil 3 times and drowned cylinders with Marvel Mystery Oil. Bagged up boat for the winter. Thinking with the cracks in the exhaust manifolds there is a good chance the block is shot yes/no? Looking at long block options because by the time I pull engine and have parts magnafluxed that is $800-$1000. Sorry for the long rant, just looking for advice on the situation from you guys. Thanks! Chris Z.

[waterlogged882]

thank you

[88 PS190]

Thinking with the cracks in the exhaust manifolds there is a good chance the block is shot yes/no? Looking at long block options because by the time I pull engine and have parts magnafluxed that is $800-$1000.

Manifolds are either ebay - or you can technically bake them then silicone bronze tig them, but by the time you're doing that you better do it yourself as the lower manifolds from sierra are sub 200 bucks.

I'd have a hard time not just buying an ebay truck engine, swapping parts and running it. I might not even swap the expansion plugs - if you decided then you wanted to build it up by all means - but I don't think you'll notice the difference between the old boat plant and a truck engine in use.

[Zs86PS-190]

I believe the exhaust manifolds are fine. I filled the cooling chambers with water and they sat with water in them for 5 days with no water leaking. I guess my main question is what is the most likely source of the water in the engine at this point with an engine that was not winterized correctly???

Cylinders all hold compression so think head gaskets are fine.

What most commonly freezes and cracks, I am thinking engine block right?

Chris Z

[woodrowskis]

A friend recommended trying to pressure with air to find the leak. Probably easiest place to connect supply is the hose at the thru hull fitting. Disconnect the hoses entering each exhaust manifold and plug. You could probably hear the air getting inside the crankcase somewhere. granted you only allow about 5-10 psig. More pressure might damage something. Listen through carb and might detect an intake manifold gasket issue. Pull valve covers, you might hear something near the heads (and pulling spark plug could narrow that down). Has anyone done something like this? need to buy $10 of fittings to get from air to the hose. need air compressor but borrow that if you don't have one.
I would have said highest percentage chance was the exhaust manifolds but you say those are good. I had an 86 almost identical to yours (color, etc.) One of the manifolds went long before anything else on mine but could have been a freeze that got it.

[bturner2]

Divorce, cheap boat and cracked anything typically add up to an non winterized boat that was neglected due to their unfortunate situation. There's typically only 2 places common for that water to come from, a head gasket (which might be possible due to overheating) or a cracked block (typically due to non or poor winterization). With the price you paid and the story that went along with it my money is on cracked block. You didn't happen to buy the boat from the ex wife by any chance did you? If so I'm all in on cracked block.

Looks like you're in SE Michigan. Around us MI Motorz is about the best place to buy re-manufactured and new marine engines.

https://www.michiganmotorz.com/ford-marine-engines-c-31_50.html

If you go down this road you may want to check with them to see if they'll cut a cash deal or what options they may be able to suggest. If nothing else they'll know the better machine shops that are familiar with marine engines to go to.

While the junkyard engine is always an option unless you really know what you're looking for and can do much of the work yourself you may find yourself wishing you would have bought new or re-manufactured. I know there's a lot of guys on this forum with mad engine building skills but I'm certainly not one of them. That being said you don't need mad skills to to swap an engine in a ProStar. Unless you're one of the mad skills guys I know which direction I would take......

[Zs86PS-190]

Thanks guys! Yes I am currently in contact with michiganmotorz to see if they can help with a less expensive 351w replacement option. Love the idea of a new 351w with GT-40 heads just don't want to invest that much in an older boat like this. Also looking at good used engine options. Anyone know of a thread with engine swap in 80's MC?

[Zs86PS-190]

Anyone know of a reason why this FORD 351W 88-93 MARINE ENGINE w/dipstick in block not oil pan won't work in my 86 P-S 190?

https://www.summitracing.com/parts/hme-dma1-gtp/overview/

Chris Z

[SSMoose]

On the Summit website, it should ask you for an application. This will give you a solid answer. The resident tech on duty probably can answer. Go to the source for the best info.

[Zs86PS-190]

Thanks Bob. Summit did not really know. They have a good stock replacement option DM06 that I am also looking at. Not sure the extra $600 is worth it for 40 more horsepower of the DMA1-GTP.

[Zs86PS-190]

Need engine experts advice

Need engine experts advice. Difference between 351w with two piece main seal & dipstick in the oil pan and one piece min seal & dipstick in the block? Interchangeable engines

[Zs86PS-190]

Answering my own post for FYI. Purchased a new ATK DMA1 351W marine long block directly from ATK (www.gearheadengines.com). Sale and shipping very smooth. The DMA1 is the newer version of the 351W with one piece rear main seal and dipstick hole in the block. Boat re-power went smoothly but was A LOT of work in one weekend. Took me a couple of weeks to get everything back on the engine ready for fire-up. After some distributor timing adjusting got new engine fired up.

Bottom line for anyone looking to re-power 1986 and older MC the newer style long block is a good replacement. Only slight modification was plugging the dipstick hole in the block. Not hard, google it.

The engine I chose DMA1 & DMA1GTP the hotter version with GT-40 heads will work just fine in these older tugs.


Chris Z

[Zs86PS-190]

https://photos.app.goo.gl/XJjVVGvg5iUF6w6h8

[Fullpass]

Very Nice & Good Job…I'm sure... most would of liked more photos, of removing engine and install and engine alignment…Great job and Welcome to the forum! You Got the skills

[Timr71]

Looks great! Congrats!