Is this the end of my V20?

[djfam]

Newly registered to this site, although I have been viewing it for years. Unfortunately, my first post is not a good one....

1983 V20 w/ 1983 Mercruiser 470 - best boat I've ever owned.

When de-winterizing my boat this week, i was running it on the muffs when it died and a spurt of water/oil mix came out of the vent hose at the top of the crankcase (next to the flame arrestor) - maybe a quart of water. I knew right away that this should never happen. The boat had been running for about 10 minutes. (It was a little rough but i figured that was just because it sat all winter). I'm trying to determine what the problem might be and i was wondering if any other V20 owners had experience with this. I'm thinking possible head gasket but also a possible crack in the block or exhaust manifold issue. Either way, I know it is bad. Anyone have any ideas?

Thanks, in advance, for your comments.

[nipper]

I had a similar experience with a 4.3 litre mercruiser engine. Unfortunately, turned out to be a cracked block, and I ended up buying a whole new engine.

[macojoe]

I had a issue like that and it turned out to be that the head rotted a hole in it and allowed water in the crank case, I replaced the head and was fine for another 2 years when the motor rotted internally and was junk!

If I was you I would remove the engin and all and fill the hole and add a bracket and Outboard, Thats what I did and it was the best thing I ever did!! and if you are handy you can do all the work yourself and get out of it pretty cheap

Good Luck

[Destroyer]

UGH!!!... Not a pretty problem. :sad: You have a clue to the problem with the fact that it's the first time you started it since the winter. Winter is hell on I/O's.. just a small amount of undrained water in the wrong spot can crack a block. Fortunately, you're not in that bad a position IMHO. Blocks are waaaaayyyy cheaper than outdrives, and if you can do the work yourself you should be able to find a good block and get by for under $500. But I have to agree with Macojoe... patch the hole, get a bracket and an outboard. You'll thank us later..

[djfam]

So guys...it never even crossed my mind to go the bracket/outboard route. I'm intrigued. How is this accomplished / what type of bracket is necessary? The other obvious question is cost. For a V20 I'm guessing at least a 150hp outboard, correct?

[parishht]

Do a search on the site, a couple of people have bracketed their transoms and documented it.
One of the best is BibShrimpins, he made his own bracket.

[macojoe]

You can get a good used 15t0 Merc for like $2000 or less!!

Fix the hole about $200 for material and your time, A usexd bracket $500 or less.
Check ebay, crigslist, local boat yards for a take off.

I had mine all set to go in a week end after I located all the parts

Go to the gallery and look at my gallery shows pic's there of my redo, ask all the questions you want, I am not the only one that has done it!!

[parishht]

Here is a link to the gallery home page:

http://www.wellcraftv20.com/gallery/v20_step

[phatdaddy]

look at it as not the end of your v-20, but the re-birth of your v-20!!

[djfam]

Some of these brackets look great. Macojoe - I am impressed with what you did.

My only thought is that it would cost me 2-3 grand to do this, and a rebuild on my motor now would cost that, maybe even less. Is it worth it? Are there any performance benefits to going the bracket/outboard route?

The boat itself is in great shape for an '83 and i hate to get rid of it, but spending a) lots of time to redo it and b) lots of money to do it - are not what I was hoping for as we enter boating and fishing season.

[Genie Aye]

Is this the 3.7 litre merc? They had real issues with the exhaust manifold rotting out--I have seen this several times with these motors. Start at the basics before going crazy. Pull the exhaust manifold and riser and inspect them--I will bet they are the source of your problem. Hopefully you did not hydraulic a rod. These are expensive engines to rebuild if it comes to that. A 150hp outboard will out run and out gun that 170ho I/O.

Good luck with the issue and your decision.

[djfam]

Genie Aye....thanks.

I had read that the exhaust manifolds were suspect on these motors and planned on pulling mine this weekend. What should I look for in your opinion? I'm sure it is hard to see inside. Do they need pressure tested and if so, how is that done?

[Road King Cole]

Hi djfam,

I'm probably not much help, but I hope you are able to save your engine without too much cost\time. I am not in the upper "bracketed outboard" club\groupie thing going on here. My previous owner had put in a rebuilt merc 470 a year or two before I bought it from him. Albeit I never had a bracketed outboard, but I am happy with the 470 set up. They sound good, sip gas and troll well. Being that I am not on a smooth lake, it goes plenty fast enough for me.

Good luck!

rkc

[djfam]

So I finally got to check my compression and it is pretty good. 140, 110, 125, 130. I'm a little concerned about the 110, but it is still right around the right margin. I am still diagnosing the issue, but I am not so sure now that I have a cracked block. There may still be a head gasket issue, but I am leaning now towards the exhaust manifold and elbow as culprits. If the water back flowed through the manifold into the engine, through a crack or busted gasket, I think this may have caused my issue. I will check this weekend if time/weather permits.

One problem I will have if it is the manifold is that it is not made anymore and not really able to be purchased anywhere. Mercruiser number is 71527A17. No-one makes them so I guess I will have to buy used on Ebay if anyone ever posts one. Can I take these to a machine shop for repairing?

[cfelton]

Djfam, did the water come from the valve cover vent connected to the flame arrester on top of the carb? Check the oil on the dipstick, see if its milky. Also see if theres oil in the coolant reservoir on top of the exhaust manifold, and was there good antifreeze in the cooling system. I'll try ta help you figure out where your trouble is. I completely rebuilt my 170 Mercruiser 3 years ago and helped my buddy rebuild his last summer, both are running strong. I love these old motors. You can still buy parts for these motors, sometimes it takes a little searching. Ive got alot of parts dealers on a list if ya need them! I had ta buy a new Mercruiser reservoir for mine when I rebuilt it. Good luck!

[djfam]

cfelton....

yes, the water came out of the vent hose that goes from the valve cover to the flame arrestor.

the coolant looks OK and I did not see any mixing of oil with it - level seems fine and it is a 50/50 mix.

Compression numbers again were 140, 110, 125, 130

I'll definitely need some parts help, especially if it turns out to be the exhaust manifold. They no longer make the one I need.

[djfam]

And the oil on the dipstick was not milky but I'll check it again since it has sat now for a few days....

[macojoe]

http://inetmarine.com/mcm37l4704854881980-1984.aspx

http://www.outdriveshop.com/exhaustmanifolds.html

I found these in a quick search, but they are not giving them away!!
I remember back in 98 when I bought my 165 manifold and it was $700 then, thats why I went outboard

Good luck

[djfam]

Thanks macojoe...

The one I need is the item for $810.50 that is listed as "No Longer Sold". The other one for the MCM 470 is no good for me.

I'll ask the question again....can I go to a machine shop and get these repaired? If not, why?

[macojoe]

Cause it is cast iron, it doesn't take to welding all that well, and how thin is the rest of it? I would hate to fix it and have it break again in short order!!
Just my 2 cents

[macojoe]

Here you go, not sure what the conversion of $$ is??

http://cgi.ebay.com.au/470-Mercruiser-71527A17-B60426A1-exhaust-manifold-new_W0QQitemZ380149149230QQcmdZViewItemQQptZAU_Boa t_Parts_Accessories?hash=item5882a7ae2e

[cfelton]

Sounds like you either have a leak in your manifold or the riser/resevior . You can buy the riser from Mercury Parts Express but you may have to buy a used manifold. If you look up into the exhaust (round ) end of the riser you may see globs of rust and scaley rust. Take a screwdriver and pick around ta see if you can pick a hole into the water jacket. If your manifold is aluminum the riser/ resevior will be cast iron. Some are the other way around. Theres a place nearby called Budget Boats in Va. that has tons of good used parts for these motors. It sounds like your riser blew through. If the riser is bad buy a NEW one, not used!