Greetings from a new boy in class!I have recently acquired a silver century plus(with clutch)1967.After much work ,especially
with the carb,it now runs well.However I have noticed that there is a 2" crack in the outer wall of the block from which water
weeps when the engine is hot.Is it possible that this is confined to the water jacket and doesn't reach the cylinder itself ?or
is this just wishful thinking on my part.Could it be welded?Other wise the motor runs well,is complete and pumps water big
time .I'd hate to end up scrapping this engine.Would anyone have any suggestions?Thanks a million.
cracked block century plus(SPCL)
Moderators: John@sos, charlesp, Charles uk, RickUK, Petergalileo
Re: cracked block century plus(SPCL)



As you can see it is rare that the cracks are on the internal side of the water jacket. Rust builds up and forces the outer wall to crack. They can be welded or siliconed up. Replacement blocks are hard to come by.
Cheers Hugo
Someone tell me how thumbnails are done please!
Re: cracked block century plus(SPCL)
Thanks for the prompt response-and all the way from 'down under'!I hope my block isn't as bad as your photos-maybe i'll angle grind the crack and then
get it welded,failing that i'll have to hunt down a replacement block-they do seem to be thin on the ground.Thanks again.
get it welded,failing that i'll have to hunt down a replacement block-they do seem to be thin on the ground.Thanks again.
Re: cracked block century plus(SPCL)
I would do it quickly before you find yourself with a more interesting motor ie early 102 (SD) <grin>
Re: cracked block century plus(SPCL)
Try JB weld the epoxy product if you can find it. This will end up badly for the cylinder, welding unless done with 900+F preheat and during weld and very slow cooling will likely do more ill than good. A cylinder showing the symptoms you describe is suffering from salt water corrosion, do a temporary fix until you can find another cylinder or motor with a good cylinder. Check it out carefully before you buy if you go this route. Pay special attention to the exhaust port area, no crack or even the slightest hint of a crack allowed.
Re: cracked block century plus(SPCL)
Hi all-I've been rooting about for another Seagull for parts-specifically that replacement Century block-and I came across a maggoty century short shaft no clutch (there were actually things living in it!)seized and with no tank.Much work has revealed
a gem to the extent that the intended transplant Donor is to become the recipient-I wonder how often that happens?Then I heard of another Motor in a shed 3 counties away- 20 Euro gets me the cleanest Forty Minus 1961.Its ending up daddy Bear Mummy Bear and baby Bear-the Fuhrer (yes dear!) hasn't copped it yet as she always sees me with one at a time-they're all the same to her!But the Garage is filling up and there will probably be trouble at mill.More about the baby 40 later-runs with great difficulty and doesn't pass water-sounds like the mother in law!
Thanks to all for good advice.
ps..could it be possible that seagulls are addictive?
a gem to the extent that the intended transplant Donor is to become the recipient-I wonder how often that happens?Then I heard of another Motor in a shed 3 counties away- 20 Euro gets me the cleanest Forty Minus 1961.Its ending up daddy Bear Mummy Bear and baby Bear-the Fuhrer (yes dear!) hasn't copped it yet as she always sees me with one at a time-they're all the same to her!But the Garage is filling up and there will probably be trouble at mill.More about the baby 40 later-runs with great difficulty and doesn't pass water-sounds like the mother in law!
Thanks to all for good advice.
ps..could it be possible that seagulls are addictive?
- RAY SWANN
- Posts: 57
- Joined: Sun Nov 08, 2009 1:35 am
- Location: International space station (toilets blocked again)
Re: cracked block century plus(SPCL)

I have four, but wife thinks I have one.
I did have one close call when I sneaked off to fetch one I had bought that had a bright orange flywheel.
She did remark "where did that come from?"
Oh I'm just looking at it for a friend did the trick.
You need a bit of camouflage,I painted all my flywheels gold,and resprayed all the fuel tanks black.
Now she cant tell one from another,so long as you only work on one at a time.
How ever you must keep shed cluttered up so she never goes in.
SOME DO, SOME DONT,THOSE WHO DONT, DO A BIT
- Charles uk
- Posts: 4972
- Joined: Wed Feb 27, 2008 4:38 pm
- Location: Maidenhead Berks UK
Re: cracked block century plus(SPCL)
Don't fix the water jacket until you've removed the all the rust inside the water jacket.
A wipe of silicon sealant will seal a small crack, once it's clean & dry.
A wipe of silicon sealant will seal a small crack, once it's clean & dry.
Make it idiot proof and someone will make a better idiot.
- RAY SWANN
- Posts: 57
- Joined: Sun Nov 08, 2009 1:35 am
- Location: International space station (toilets blocked again)
Re: cracked block century plus(SPCL)
This may or may not help.
Some years ago the water pump on a Perkins inboard diesel that was fitted to my boat cracked into 2 pieces and was made
from cast iron.
New pump was £100+
A boat owner in the marina told me don't worry I will take it to work and get it welded.
Came back as good as new,re fitted it and its still OK 9 years on,I don't own boat any more but new owner
moors near me and he has had no problems.
When I asked him how he had welded it he said he used a MiG welder.
Regards
Ray
Some years ago the water pump on a Perkins inboard diesel that was fitted to my boat cracked into 2 pieces and was made
from cast iron.
New pump was £100+
A boat owner in the marina told me don't worry I will take it to work and get it welded.
Came back as good as new,re fitted it and its still OK 9 years on,I don't own boat any more but new owner
moors near me and he has had no problems.
When I asked him how he had welded it he said he used a MiG welder.
Regards
Ray
SOME DO, SOME DONT,THOSE WHO DONT, DO A BIT