1987 268 Searay Sundancer Bad Motor..Need help and suggestions!!

G

garyc61

New Member
Feb 21, 2011
25
Illinois
Boat Info
1987 Sea Ray 268 Sundancer
Engines
Single 454 Merc Cruiser
Hello everyone.I was new to this site last year when I purchased my first 268 Sundancer.After a bad year of boating I am at a loss.My engine 7.4 454 mercruiser hydrolocked first time out.Lost that vacation.Drained oil and new tune up and got it running.Found no shutters in exhaust.Installed new shutters took it and again water in cylinders,overheated and locked up.I broke teeth on the flywheel trying to get it started to get in to marina.I am told the 454 was a bad design for this boat and not worth rebuilding.I do not know much about it and would like to know what is best.I invested a lot in this boat,New windlass,New 2011 Phoenix trailer,Interstate batteris x 3.Do I rebuild and by whom and where.Do I try and replace engine myself?I live in Central Illinois and wife has had enough of me and my boat.Dealer offered me $2000.00 trade for boat and trailer.Any help would be greatly appreciated.Gary L Cooper:huh:
 
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First off you need to find out where that water came from , like the exhaust manifold maybe , you dont want the same problem with your new motor. i would call Jasper or any other company you like and get a long block from them . with new manifolds of course . www.jasperengines.com
 
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The 454 is not a bad design. The 454 has a ton of low end torque. The Merc install however, was a POS. You need at least 13 inches above the water line to avoid reversion (water getting sucked into the engine). The 330's were notorious for this. You may just need riser spacers and a new short block. That's all the dealer is going to do.

Jasper engines are good. Marine power are also good.
 
Don't panic. There is nothing wrong with the 454. In fact, as mentioned, it is a very capable motor. Find out where the water is coming from (probably bad headers or risers) and correct. Many 268's run with that engine without riser extensions with no problem. So, I doubt you need riser extensions, but it is remotely possible.
 
I had a 268 with the 7.4 and never had any problems with the engine during the 5yrs I had it and there is an identical one at our marina that just finally rebuilt the engine after 3000 hrs! It was the right single engine for the boat, but the twin 6's were a better option (although I wouldn't want to work in that ER). The more likely problem was leaking exhaust manifolds. I'd just swap the engine for another 7.4 and get new manifolds/risers. Maybe check out the one piece stainless manifolds/risers that some members have - they're from Australia and look like they solve many water intrusion issues.

Hang in there. This is assuming that the rest of the boat is in nice condition. If it needs updating too, it might be time to cut your losses.
 
Thank You so much to all who replied.
I love the boat and it is in very clean condition.The exterior is buffed to a high shine and has never had any mods to it that were not made for it.No holes cut in the dash no drilled holes just a sharp looking boat.I tried to load photo's but not sure how.Are there any special tools needed to do the engine change?
I have a shop with plenty off tools and have done many automotive engine swaps over the years but No boats.It looks basic but just want to be sure.I am not one to say I know it all.
Thank You,Gary
 
dpmulvey said:
The 454 is not a bad design. The 454 has a ton of low end torque. The Merc install however, was a POS. You need at least 13 inches above the water line to avoid reversion (water getting sucked into the engine). The 330's were notorious for this. You may just need riser spacers and a new short block. That's all the dealer is going to do.

Jasper engines are good. Marine power are also good.
Click to expand...



But he is working on a 1987 model 7.4 Merc. I thought the reversion/water intrusion issue was only on the late '90's 7.4's where Merc messed with the valve timing to try to scavenge exhaust gases out of the cylinder more thoroughly to try to get the 7.4 to pass emissions requirements. There are and were a ton of perfectly fine 7.4's out there with no water intrusion problems, up to about 1997-98 (?). The only water problem most experienced were when the risers and manifolds were not checked and changed when needed.

As you guys are saying, this is an easy one. I'd install a new long block put the old accessories on it and go boating.
 
If you like the boat and she is in good cosmetic shape, just replace the motor! The cheapest way to do it is purchase a replacement 7.4 marine long block and switch all of your components over. Another option is to buy a reman engine "package" direct from a mercury dealer (Doug Russel, Michigan Motorz, etc) with all new accesories and compenents and pay a professional to install it to get the 3 year warranty from Mercury. Professional installation is around $1250-2000 depending on the area.
 
garyc61 said:
Thank You so much to all who replied.
I love the boat and it is in very clean condition.The exterior is buffed to a high shine and has never had any mods to it that were not made for it.No holes cut in the dash no drilled holes just a sharp looking boat.I tried to load photo's but not sure how.Are there any special tools needed to do the engine change?
I have a shop with plenty off tools and have done many automotive engine swaps over the years but No boats.It looks basic but just want to be sure.I am not one to say I know it all.
Thank You,Gary
Click to expand...

Replacing the boat engine is less involved than a car engine (IMHO), so you should have no problem. I haven't done it myself, so I'll let others give you the proceedure - better yet, do a search on engine removals on CSR. Once the out drive is removed, electrical cables, fuel line, shifter and throttle cables, the only thing holding the engine in are the motor mounts...
 
Swapping a single out of that hull is so simple. My only suggestion is to take lots and lots of pictures of the engine room from every angle, and shoot some video too. It may prove helpful during re-installation. Oh, and what ever you do, don't forget to label every single hose, cable and wire that you disconnect. You will thank me later! If you have as much experience in automotive engine swaps as you say, you should be able to have that old engine out in an hour, assuming you have the proper crane gantry and tools. Have someone ready and willing to help, and for God's sake, be careful! Good luck!
 
You Guy's are Great!!
I do have plenty of mechanical experiance and I am a Maintenance Engineer for McDonalds Restaurant Corp.I jumped right in to it after reading all the reply post's and marked everything with wire labels,took note's and photo's,and now I am ready to lift it out.I have a lift that is 4 ton's and plan on removing it this Saturday.I am excited to get this done and done right.Another question I have is regarding my exhaust I have No idea if my exhaust is bad so I am planning on replacing with quality part's such as Mercruiser but is there anything I can do exhaust wise for better performance at this point or just stay stock and stay safe?Gary
 
For exhaust manifolds/risers check Hi-Tek out...

http://www.hitekmarine.com.au/products.htm

There have been a couple of CSR members that made the upgrade to these bad boys and they seem pleased with the quality of the product. If I would have known about them before replacing mine with stock, I would have seriously considered making the switch!
 
Hey Guys
All went well.Took plenty of notes and photos and out it in came in less than an hour.No scratches or damage to the me or the boat!!.Got a list together of New parts to reinstall instead of the old ones such as fuel pump possibly water circ pump,Coil is old so I ordered a New one.I Found a highly respected engine rebuilder in South Bend Indiana who is doing my rebuild and it will be a turn key rebuild nothing to adjust when I get it back just drop in and go to the water.Hope this is the right Forum by the way to keep you guy's posted.Gary
 
Well it is a Great day!!Motor came back complete rebuild on 9-1 and is in the boat and running Great.I replaced all hose's belt's new bolt's we are ready for the water.I will try and post photo's an my profile.Thank You all for the support and confidence to go through with this.I am excited.Take Care,Gary
 
Great to here your back on the water and running. Pics would be great. Did you use your original block? What else was replaced externally?
Thanks
Matt
 
Well here is a list.I used my original block and turned the crank after that head's and all internal parts are New.I also upgraded my intake and carb with an Edelbrock intake and Holly carb.The ports were opened up in the heads for more flow and a little bit more cam.Nothing to make it a racer just perform better.Externally because I trailer to and from the lake I added 3 inch Mercruiser riser's to prevent any water from entering on a steeper grade dock with New Mercruiser elbow's,exhaust manifolds.curve pipe and bellow's.All the hoses belts,nut's bolt's were replaced along with new mercruiser fuel pump,coil,water pump and had the original alternater and starter rebuilt.While the motor was at the shop I redid the engine compartment.Cleaned up the wiring and installed new wire clamp's new bilge pump and hose then ran all the wire's down there nice and straight.
 
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