Saving Old Seagulls

After of 25 years of storage I blew the cobwebs off my Silver Century Plus. I refilled the fluids and it started up with the second pull. The water flow out the bottom of the block slowed a bit as she reached operating temp. I then noticed a small drip of water/steam coming out of the head gasket area at the top. Does this mean I am going to have to source a new head gasket and remove the "do not remove" head? Or perhaps just believe it's just a additional means of cooling the cylinder block and run the motor as is... The plug was normaly oily and did not indicate water in the combustion area.

Thanks for reading,
Francis from the central coast of California

Hi Francis

Not bad, 2nd pull! First thing, you can get a head gasket no problem, I wouldn't let it run like this, probably one of the more experienced guys will give you advice.
Good luck. I'm sure it will have a happy ending.

Gerard

I own a silver century plus and it does the same, after a bit of running it stops leaking so if it is not broke don't fix it

Hi Francis.

If all you have is really just a drip or a little ooze, it may not be worth opening it up for that. On the other hand, if you're really pouring water out, you may not be saturating the entire cylinder with H2O the way it should do so. That is to say that while running at speed, there ought not to be steam coming out from anyplace if the block's being cooled properly. May be the "steam" is the water fizzing off when it hits the hot cylinder head fins; Im a bit surprised that they're really hot enough to do that unless you're working the heck out of the engine.

If you were to drop to an idle so that water stops coming out the regular exit hole, the water that's left in the block is going to start to boil off and produce steam. Spool up the throttle, and steam ought to dissappear as water displaces any empty space inside and, moreover, cools the cylinder properly.

If you're new to Seagull maintenance there are some things you should look into before doing anything.

The main thing is that the "Do Not Remove" warning is there because of the tendancy for the head bolts to corrode into place on the deep end of the threads. There are one or two bolts in particular that are known to stick (can't recall which) because they actually enter the water jacket. If you've worked with long, thin bolts before, you'll recall that the bolt head will appear to turn when we think it's coming loose and then snap off. Loads of penetrating oil to begin with can't hurt, whether it's frozen on or not. One can invert the engine and fill with WD-40 or Diesel for a few days as a precaution and as a possible hedge against possible trouble.

If you look on this board for cooling problems, the more aggressive solutions involve head removal; read them and see if this is what you want to be getting into for the level of leak you have. If you're not losing compression because of it, and not going to use this regularly on a boat other than showing that it works on occasion, then it may be well enough to let it ride. From a mechanic's point of view, you may want to fix it because it just isn't all that it can be though I've done stuff like that and ended up with broken stuff.

There are solutions to a snapped-off bolt. Just be prepared for that level of repair from the beginning as if it's a given that such is part of the job. If all works out easily without restorative work required, then that's a big bonus.

You can get a manual from John the site owner that'll cover lots of important maintenance stuff. For the cost of the mailing (quite reasonable, I might add) you could also get the head gasket as a conversation piece & for the contingency that you actually go ahead with the repair when you get bored over the winter.

Ted

Newark, Del. USA

You could always just tighten the head bolts a tad.

After a bit more maintenance, such as blowing compressed air back thru the water spit outlet in the engine block, the problem seems to have resolved itself. No more water and steam is coming out of the head gasket and the flow of water out the block is at a brisk flow, cooling the engine to a much greater degree. I did tighten the head bolts a bit just for fun…
All I have to do now is make a higher motor mount on the engine well of my 20 foot surf dory and I’ll be putting around the pacific.
Thanks for all the info…
Francis

Francis post a picture of your "surf dory" we don't know what one looks like.

This what we call a Surf Dory

Nice looking hull what's their design purpose?

I'd take it carefull when in shallow water you've got 14 inches of gearbox hanging below that hull & no provision for it to tilt, you might need to do some woodwork & fit one of those lifting transom brackets that are used for small outboards on sail boats.

http://www.youtube.com/watch?v=qzPNHE5ka9I

Life guards used to use surf dorys for beach rescues, now it's more of a sport. The ones in the video may be slightly smaller than my 20 footer. These also have a deck above the water line and scupper holes for quick drainage.

When I come to shallow water I will just pull the pin and pull the little motor up on the deck, might make a box cradle to keep her from rolling around and oozeing fluids on the deck.
The 11 foot oars will have to suffice at that point.

Hey,

Nice looking mount for the engine! I've got a hair-brained idea for dealing with the engine in shallow water that might be worth making a few drawings, at least.

Consider making a vertical-sliding rack out of wood (or metal) using tongue-and-groove cuts (or similar) that holds the Seagull on the sliding member. One could counterweight the engine by using two automotive rear hatch lift-gate pneumatic pistons from your favorite auto store. I used one such piston on a transom mount for two seasons in salt water, springs having not been included on our mount. There were only minor traces of corrosion evident over that period; stainless pistons are on the market for more money of course.

Anyway.... something like that could be made to simply lift the whole deal up only enough to clear the bottom hull. There would be no messing with the weight, the leakage, or the potential dropping of the beast upon your nice boat finish while negotiating the surf, inbound or outbound.

Just a thought.


- Ted

I’m kind of hijacking my own thread, I hope that’ ok with you guys… I put the surf dory in the water on Thursday. A little spot called Morro Bay, CA. Its claim to fame is a large roundish volcanic rock at the entrance of the bay. The fog had rolled in so it was barely visible. Once in the water I noticed several things. First while rowing, with the Seagull in the water I would go just over 2 miles per hour according to my GPS. (I guess that’s 3.2 KPH for the rest of the world.) When I stopped pulling, the boat hit the brakes. Once I pulled the Gull out of the water, I could easily make just over 3 MPH or (4.8 KPH) and could glide a ways between strokes. When I pulled any harder or faster water would come splashing up the well and I believe that the opening was slowing me down. I may fashion a plug to cover the hole to streamline the hull and prevent the water from splashing. Once I started her up, Idle speed was 4 MPH (6.4 KPH). Half throttle gave me 5 MPH (8 KPH) and full throttle was 6 MPH (9.6 KPH). This is what my hull speed should be, considering a 16 foot waterline.
I did experience some overheating, the motor would pump fine for about the first half hour, then less and less water flow until steam was venting out the block. I shut her down and let her cool down while wondering if I picked up some seaweed. Not finding any blockage I restarted her and there was less than the normal stream of water exiting the vent hole of the engine. She quickly overheated again and I returned to using the oars. After she was completely cool I saw the normal to me, amount of water…
I am of the opinion that the water pipe fitting is loose and therefore giving me erratic water pump performance. I will pull the motor apart and check.
I was also shocked at how loud the motor is. I certainly don’t remember this amount of noise 25 years ago when it sat, mostly unused, on the back of my sailboat. Perhaps that it is in a well amplifies the volume exponentially. In any case I am going to address the sound issue after I correct the overheating problem.

Noise - You might try plugging the two relief holes on the exhaust tube. I used a fine thread tap of appropriate size, 10-32 I think, and fit a couple of 1/4" brass screws to fill mine. That eliminated that source of noise which may indeed be amplified by the well in your boat, plus you'll drive most of the exhaust down into the water and minimize the black snot which fouls your well. Before you replace the exhaust tube after fixing your cooling issue, run a generous bead of hi-temp RTV silicone around the exhaust flange and on the mating portion of the inside of the tube to eliminate the black drool from that area. Sealing the joint at the bottom of the exhaust tube wouldn't be a bad idea either.

Closing the relief holes seems to take a couple hundred RPM off the top end as measured by a digital tach, but otherwise I've experienced absolutely no difference in runability. If you get it a situation where you absolutely need that extra few inch/ounces of torque, the screws are easily removed.

I troll for hours with my Forty+ and the reduction in sound levels at idle speeds is very apparent. Not so at cruise speeds where intake honk and mechanical thrashing noises dominate.

For the noise problem
I plugged up the two holes and sure enough, it's a bit quieter. I am thinking there might be some more additional options however. I am considering adding an expansion chamber from a 100 cc go cart, I am thinking that one tube inside of the original might quite things down even more, and while I don’t need any extra power, if I get the length correct it might run smoother.

I found out where my overheating problems were coming from. I pulled the head off, the bolts came off without a problem (guess I used anti-seize when I think I played with it back in “75”). The cooling passages were packed with crud which I am slowly removing with screwdrivers and other sharp bits of metal.
Since I have everything apart I am going ahead with my plan to shorten the motor by 7 inches. That will eliminate the need for the extra wood on the motor well raising the motor. I am also considering lengthening the motor well to allow tilting of the motor. A shorter leg on the motor will allow less cutout of the motor well. Wish me luck…