Loss of power in Century

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OverseasSoul
Posts: 24
Joined: Tue Aug 05, 2014 3:21 am
Location: Charleston,SC

Loss of power in Century

Post by OverseasSoul »

Hello everyone, this is my first post.
I've spent 10 years restoring a Lightning sailboat (11900 - built 1972) for daysailing around Charleston Harbor in South Carolina and we have sailed it with great success a few times. Getting it out into the harbor into the good winds down a mile long tidal creek is a challenge. My wife and I effectively emigrated from Oxford in 1992 seeking our fortunes and the US has been kind to us... though I miss England and much what is represented in these august pages a great deal. We have 3 teenage boys - and now will probably stay here.
To solve the issue of a motor for our Lightning, I researched and chose a Seagull - it seemed to fit our values well and I loved the idea of making something old work well again, and that it could take a dunking if we capsized. I have already ruined a $20k Honda engine when our beloved C-dory sank at the dock in a 7 inch rainstorm when the bilge failed ( that's another story).
So a week ago I looked across e-bay and craigslist and found in Raleigh NC a Century 100 Long shaft CPCL 566C5 made in March 1965 -the pics seemed to show it in excellent condition. Fully chromed exhaust and drive shafts with little wear, no gunk of any kind. Started on 2nd pull when I visited ( he started it out of a barrel and I asked him to shut it down right away). Got it as a trade from a "guy in California" and I imagined a decade of use on lake Tahoe followed by 30 years storage in the boat shed under oily rags. All good. Seller told me it needed "1:25" mix. Paid $460, probably too much, but it was close and other options I'd seen around $300 needed $150 worth of shipping or travel. There was a beautiful one fully restored in Florida by clearly an expat Seaguller for $650, but that was an 8hr drive away and the price seemed firm.
At home measured up the transom of my Lightning and realized would need to raise the long shaft to keep only an inch or so under the waterline for easy starting, so bought an expensive mount that raises and lowers ( Garelick) and set it with a back plate. Looked great. Then started on the Century - took the Villiers carb off, cleaned all that I could see but there was no gunk. The Taper needle had a "3" on it, so 1:10 is the correct mix and the first doubt about pedigree crept in. Cleaned out the fuel system ( very dirty), put a gunk removing cleaner in the cylinder head, fitted a new Champion D16 plug (gapped to 20), stripped a clumsy layer of paint off the fuel tank to reveal a beautiful old brass and black lacquer, cleaned the fuel cap - good as new- and mounted it on the Lightning for a barrel test (able to lower it using the mount into a 20 gal barrel). Used Penzoil premium marine 2 stroke at 10:1. Started on 2nd pull. Felt like a hero and my family responded as such. Great videos, and perhaps will post one to YouTube. Engaging the prop splashed the water out of the barrel. Cooling water flowed well - like a pencil. Could not find SAE140 anywhere even to order, but lower unit was leaking some brownish stuff in the barrel test, so I thought there was enough lubrication of some kind to give it a safe try...
So after that preamble, yesterday I put the Lightning hull (no mast) in the water in our local creek ( Hobcaw creek on the Wando river) for a boat test. I stored the Seagull on its side for the short journey to the boat ramp to save my transom. At the dock, with family videoing .....wouldn't start. Got son to sit on the bow to lift the stern out of the water. Did start after 20 pulls or so. Then when I engaged the prop, power faded away and we got 5 yards and cut out. Was mystified - Started again though, and was more careful with the throttle, engaging prop and throttling up quite quickly to apply power and we were off - but only got up to about 4 knots, certainly not hull speed. Hull only weighs 700lbs or so, and I expected more from my "barge pusher". Subsequent starts were tricky - 20+ pulls - but we got home back up the creek. No longer feeling like a hero and had to buy some flowers for my wife this morning (we are on stay-cation).
So any help would be great from this forum to get the engine going and put me back in good standing with my wife.
So issues now:
1) Perhaps the unknown lower unit gearing has a high resistance and needs that SAE140 oil. I will order some online. That might explain the soft torque and low performance.
2) Seemed very sensitive to water depth over exhaust pipe and back pressure - son on bow pulled transom higher, and that seemed to help, but did not cure.
3) Could loss of power be low compression - piston rings worn? Will test if I can find the tool. Looking inside the block it seemed clean and the original spark plug was clean.
4) Is this most likely a fuel supply problem? None of the above explain the poor starting. I can see some debris back in the hose,and know that the mesh on the fuel tap is shot. I didn't clean the jet when I took the Villiers carb apart, cleaned only what I could easily see taking the top cap and bulb off. What would the effect of running at 1:25 mix be? Seemed to start OK in the previous owners hands - had I been too cocky?
So lots of history and questions here. I hope you can all help - I would very much like to put my 49 year old motor on my restored 42 year old sailboat and sail it around Charleston harbor by a couple of 55 'ishers :D
Thanks to you all- I've loved following your stories, have read every word of the SOS and other sites, and enjoyed the video's n YouTube. I feel connected back to the UK again, through my old engine..
Iain Sanderson.
Michael
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Joined: Sun Oct 29, 2006 1:38 am
Location: Bermuda

Re: Loss of power in Century

Post by Michael »

Did you try using partial choke to see if that would improve things? If it did, perhaps carb is not as clean as it needs to be.
Have you clecked and cleaned the points? If it has been sitting for decades, these will most likely be dirty and cause no or erratic spark.
Did you clean the fuel tank and the fuel filter and tap?
BTW, there should have been no need to buy the garlick mount. You could have just raised the engine up and then clamped a spacer around the driveshaft tube and above the swivel assembly.
Keith.P
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Re: Loss of power in Century

Post by Keith.P »

It all very much sounds like you have low compression on that motor, with good compression you can have the water up to the base of the cylinder and it will start or run fine.
Compression test the engine if you can, I think new rings are the way to go, I don't think its a gearbox problem.
Put a jubilee clip around the drive tube or something similar so you can adjust your transom high to a suit.
OverseasSoul
Posts: 24
Joined: Tue Aug 05, 2014 3:21 am
Location: Charleston,SC

Re: Loss of power in Century

Post by OverseasSoul »

Thanks Michael and Keith,
I did clean out the fuel tank and carb, but have not checked the points. I love the tip about raising the engine swivel on the drive shaft with a jubilee clip - That will get me extra inches. The Garelick mount is still necessary - it was the best way to spread the weight on the transom of the sailboat (balsa core between two skins of fiberglass, outer skin only 1/2 thick - not designed for a motor). It also lifts the Seagull well out of the way for sailing and leaning over.
Partial choke did not help - I fear the cause of the loss of power is the piston rings and low compression as suggested. I'll find the right tool tool to do so.
Here's a YouTube of the event, apologies in advance:

https://www.youtube.com/watch?v=bHO49bN ... l--qb6X4xQ

Iain.
Michael
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Location: Bermuda

Re: Loss of power in Century

Post by Michael »

If you are familar with working on small engines such as this one, you should be able to gauge compression by turning the flywheel by hand and seeing if there is much bounce to it as you roll it through the compression stroke. If you can spin the flywheel by hand without feeling much resistance due to compression, then this could be your problem. Does the engine idle well?
You could trying running some seafoam or similar carbon remover/cleaner through the engine to see if that helps
OverseasSoul
Posts: 24
Joined: Tue Aug 05, 2014 3:21 am
Location: Charleston,SC

Re: Loss of power in Century

Post by OverseasSoul »

Thanks Michael,
I'll go out and try that now. In the meantime I've posted another YouTube of our first Bucket Test (preceded the boat test and was a stunning success). Don't know why the boat test was so poor..

http://youtu.be/wt9uNihrNqU


Iain
Michael
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Re: Loss of power in Century

Post by Michael »

One other thought. Can you detect any side ways movement of the crankshaft? Grip flywheel and see if you detect movement sideways. Givem that PO ran on 25:1 mix, it is possible the carnkcase bushes are worn, allowing loss of primary compression.
OverseasSoul
Posts: 24
Joined: Tue Aug 05, 2014 3:21 am
Location: Charleston,SC

Re: Loss of power in Century

Post by OverseasSoul »

I mounted the engine back up and spun the flywheel by hand as suggested. It has a resistance at compression of about a pound force ( my judgement) that can easily be turned through. If flicked and spun ( hand on for an instant) it bounces back from top compression, but quite meekly.
OverseasSoul
Posts: 24
Joined: Tue Aug 05, 2014 3:21 am
Location: Charleston,SC

Re: Loss of power in Century

Post by OverseasSoul »

Michael, no detectable sideways motion of the flywheel on the crankcase. The crankcase looks new - no visible wear at all. The PO only had the engine temporarily to sell - he bought and sold old engines, and had a collection of vintage chain saws. The engine is in amazing condition for 49 years old - If I can work out how to post an image I'll show you.
Iain
Keith.P
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Re: Loss of power in Century

Post by Keith.P »

Under the text when posting you will see upload attachment, for adding pictures.
Normally if you can turn the flywheel with one hand easily, then its a compression problem, best have a look for any weeping from gaskets or crank, but with a depth running problem, it's usually one or the other.
The motor looks brand new, nice find.



P.S. try to keep the revs low when not in gear, easiest way to shorten its life.
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Charles uk
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Re: Loss of power in Century

Post by Charles uk »

Now tell us about the boat, 700lbs, how long & wide & whats the approx weight fully laden & perhaps the boat test question might answer itself.
Make it idiot proof and someone will make a better idiot.
weddigen
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Joined: Sun Mar 07, 2010 12:23 am
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Re: Loss of power in Century

Post by weddigen »

I know it sounds hopelessly obvious but did you open the vent in the filler cap before the boat test as everything seemed fine in the Barrel outing? I still make this mistake from time to time!I have restored three of these motors thus far and still marvel how gunk magically appears from nowhere and causes this kind of hassle.Strip EVERYTHING in the fuel system yet again and don't forget the HT spark lead connections and points gap and condition.Somehow I doubt the compression explanation -just a feeling I get from the U tube shots.good luck with it -if this was a modern engine it could be any one of 30 issues -with a Seagull things are a lot simpler!
OverseasSoul
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Joined: Tue Aug 05, 2014 3:21 am
Location: Charleston,SC

Re: Loss of power in Century

Post by OverseasSoul »

It's entirely possible that I didn't open the top fuel tank screw. I did notice a 1 inch air bubble in the fuel tube and wondered why it didn't go away - it did eventually. Caught up in the moment. But after eventually starting I went on quite a long run for about 1/2 mile then stopped voluntarily. Would it do that if the tank was sealed?
Regarding boat weight. The Lightning hull is 19ft, class weight is 700lbs with the mast. With me it, engine and mount- 900lbs total. The lightning is a performance sailboat - moves on a whisper win a very smooth Hull.
Thanks for your help. I really hope I was incompetent and left the cap screw right. I have no memory of undoing it.
I've just got a compression kit- rented from O'Reilly's chain autopart USA for free. Pay a deposit, keep 48 hours, return for no charge.
Will let you know what the numbers show and how the spark is in a few hours.
Iain
OverseasSoul
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Joined: Tue Aug 05, 2014 3:21 am
Location: Charleston,SC

Re: Loss of power in Century

Post by OverseasSoul »

Ok got the compression tested - 28-32psi with various strength pulls. Spark was white/yellow but consistent - wouldn't say strong, but don't really know what strong is. Tried to open up the fuel again, and noticed it barely flowed out of the tank into the fuel line even with the vent fully open, and there is debris in the line. So seems there are a range of issues. Is that compression OK? Seems low on the gauge.
Iain.
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Charles uk
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Re: Loss of power in Century

Post by Charles uk »

Too much load & Keith was right, excellent compression 75 lbs, poor around 45 lbs, they don't usually run much under 40 lbs.
Make it idiot proof and someone will make a better idiot.
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