Rebuild or replace the engine

Oct 30, 2019
64
Hi all,
My Vega still has the original Volvo 2cylinder engine in it. It
runs good and I really like it. I know that the pistons and bearings
will at some point get sloppy and the engine will need to be rebuilt or
thrown away. I have heard on this list and by some others that they
would buy a new engine if it cost too much to rebuild the Volvo. I find
that surprising! One of the big reasons for buying Volvo in the first
place was that it could be rebuilt probably several times or more. It
should be the last engine a person ever needs to buy especially when you
own a boat that like that with care should need to be replaced.
I would not even concider replacing my engine with a new engine.
I have owned a couple of them and they are as good as a cheap little
engine can be. But they are only half as good as an expensive engine
like a volvo is. If I had a yanmar I would definitly not rebuild it
unless I was going to do it myself which is what I would do. The
Volvo with it's heavy flywhell and the carry trough of that weight makes
the engine run smooth but the heavy flywheel also provides the cary
through to make it possible to hand crank. MY 5ft 3inch wife can do
it. That is a huge amount of insurance when off in a distant spot and
need the engine and with me nursing a broken are gotten in a fall in
heavy seas. The batteries are to dead to crank an engine. If you are a
big man and strong as an ox you may be able to crank a very small modern
engine. I'll bet your wife won't.
The Volvo would likely have cost double what the yanmar costs and
with good reason. It's twice the engine where quality is concerned. The
big flywheel controls the banking , slugging and ratteling that yanmar
does that causes them to self destruct. A big flywheel is the most
important part of a one or two cylinder engines in giving it a longer
life. The bearings have to be bigger to carry the heavy flywheel and
they cost money.
I am not putting the littl light engines down they are good
serviceable engines and the price is definitely right. The Volvo twin
cylinder engine is not a good engine it is and excellent one.
If I have the choice of rebuilding my engine for the same money as
a new small engine I will choose to rebuild. My engine has been slowly
rusting away for 35 years and it's block is still heavier than a modern
small diesel. After all their is nickel in that cast iron.
I live in a small town where we have a lawn party every year and
there is a tractor pull and a display of old engines. Some of them are
marine engines and they are all running. I talked to a diesel mechanic
that brought his engine in to display and run. His engine had been in
his Grand fathers boat and in the family nearly a hundred years his
Grandfather and his father used the engine to fish for a living. It is a
small single cylinder gasoline Grey marine. That engine pushed their
work boat everyday six days a week for close to a hundred years. They
rebuilt it about every 10 years. If Stan had to get rid of his wife or
his engine, guess who would go? His Grand kids are after him to build a
boat to put it in. He found another engine of the same make to use. He
dosen't want to risk the original to a possible sinking.
I think the Volvo is just such an engine and if she is retired
befor fifty years of use it's a shame. The good news is if you don't
want to rebuild, there are hundreds or thousands of good Volvo engines
laying around diesel shops that were pulled out and replaced years
before they needed to be. If your Volvo is blowing some blue smoke and
the mechanic tells you its worn out, keep it in the builge another
several thousand hours. As long as she starts Ok she likly is OK. A
Volvo runing at 1700 rpm don't blow up, they finally just get impossible
to start. This is because the rings are worn and their is just not
enough compression to fire up the engine. They only need three things
,air, fuel and compression. Just be sure that is when rebuilding is
neccissary. It might be that the injector or the fuel pump might need a
little work.

Doug
 
Nov 8, 2001
1,818
Hi Doug

Without exception, every vega owner I know that have changed their old Volvo for a new Beta have all said "Wish I changed 5 years ago"

Had my Beta in for 12 years now, starts first turn of teh key, easy to service, parts available at reasonable cost....

Can just imagine everyone keeping their 45 year old cars going instead of driving a modern one -

Wait until you have to buy spares for your old Volvo - MD6A Injector Pump (If you can get one) = £1500

Afraid i totally disagree with you. Nothing to do with me supplying Betas either!!

Cheers

Steve B
 
Nov 8, 2001
1,818
Hi Doug

Yep, the Beta is based on the Kubota.

Anyone that can rebuild an engine impresses me, my enginering prowess is pretty low on the scale. I know a few guys that can and always ask their advice.

Always say each to their own and you obviously enjoy rebuilding engines, not all of us have that ability or skill. Obtaining spares for your MD6A/7A by buying an old engine is the best way (So long as the bits you need are serviceable!)

The Beta does not handcrank, that is a fact BUT the only time I hand-crnaked my Volvo MD6A (over a 10 year period) was when I proved to myself I could do it! There is a knack to handcranking which took me a while but very satisfying when you can do it. In the 12 years I have had the Beta installed I have never had to handcrank it to start so with the 10 years I had the Volvo that is 22 years of Vega owning and not having to handcrank the engine to start. If it is that important to anyone then carry an extra battery (only needs to be small - 45AH) for peace of mind. Another car analogy - My Dad's car could also be handcranked to start, don't see many nowadays!

Vive la difference........

Steve B

I already have an injector pump it came on an engine I bought used. I
would be willing to pay up too about $6,000 to rebuild if I had to, as a
new engine would cost about that, If I rebuild, I will do it my self
that costs nothing except parts. Who builds, Beta, is that Kabota?
Can You hand crank your Beta? Doug
 
Oct 31, 2019
230
Doug - I agree that the MD6 is a keeper. I had mine rebuilt last year- bearings did not even need replacement after 30 years of abuse. My local diesel injector shop replaced all the internals on the injector pump for $800 CAN the year before. I think that motor will outlive us all now. Trevor V2915





From: AlbinVega@yahoogroups.com [mailto:AlbinVega@yahoogroups.com] On Behalf Of Steve Birch
Sent: July 20, 2010 6:18 PM
To: AlbinVega@yahoogroups.com
Subject: Re: [AlbinVega] Rebuild or replace the engine





Hi Doug

Without exception, every vega owner I know that have changed their old Volvo for a new Beta have all said "Wish I changed 5 years ago"

Had my Beta in for 12 years now, starts first turn of teh key, easy to service, parts available at reasonable cost....

Can just imagine everyone keeping their 45 year old cars going instead of driving a modern one -

Wait until you have to buy spares for your old Volvo - MD6A Injector Pump (If you can get one) = £1500

Afraid i totally disagree with you. Nothing to do with me supplying Betas either!!

Cheers

Steve B
 

n6ric

.
Mar 19, 2010
208
Question for the group. While there are those for keeping the MD6A and those for replacing it, my question is around replacing the Combi. If I keep my MD6A, is there an easy way to replace the Combi? I take it some kind of transmission would have to be added? My engine has very low hours and I was able to crank it over (after it sat for 10 years) with the hand crank so I know it isn't frozen, but given the limited performance from the little 2 blade prop, and my concerns about most mechanics having never heard of one, I want to install a 3 blade Max-Prop. This is the main reason I'm considering replacing the engine. Thoughts?

Thanks,
Ric
s/v Blue Max
# 2692
 
May 30, 2006
1,075
The system you describe is what i have.
When I inherited the boat, it had the transmission installed. There is a 2:1 forward/reverse transmission (gearbox) for the MD6A. ...........But somehow, the previous owner kept the combi gear ratio of 1.41:1 intact, making my prop spin faster and limiting my prop choices..........So I ended up with the max-prop 3 blade which solved a lot of my problems and it is rated at quite high rpm...........Call marine parts express, they may have a gearbox for you.
roy
 
Oct 31, 2019
163
I know it's definitely possible/practical Ric, because Spring Fever's fitted with a 'traditional' gearbox, albeit with a two bladed rather than three-blade prop - based on experience, I'd trade the two blader's better hydrodynamics under sail, for the increased grunt of a three blade prop when reversing.

Sadly, I can't give you any details of what gearbox is fitted. A previous owner was given the MD6A engine, including its gearbox, 'for spares' but having discovered that this scrap engine was actually in better condition than the one then fitted to SF, he just replaced the whole thing; as a result, we have an engine which whilst still running well, is actually older than the boat!

Bob Carlisle
Spring Fever 1776