Beta diesel corrosion

tadpole

New member
Joined
2 Aug 2001
Messages
65
Location
West Dorset
Visit site
Has anyone had a problem with corrosion on Beta diesels. On returning to my mooring one day I found the engine compartment in my Pageant covered in soot, oil and grease. My friendly local engineer told me he was astonished that a so-called marine diesel had no helicoils where the heat exchanger is attached to the block and all the threads had been eaten away by corrosion - the result of poor design.
Result: a £180 bill. The engine is a 13HP twin, only three years old and little used. Potential purchasers beware.
 
G

Guest

Guest
I suspect that your friendly local engineer is talking bo....ks. Helicoils are primarily used to repair threads, and whilst they might not corrode being stainless, the metal they are screwed into would be exactly the same and would corrode in the same way with same result

In the old days, diesels were big heavy lumps of iron, that might corrode on the surface but lasted for ages. The Beta (along with most others) is based on a lightweight Jap diesel which performs excellently but cannot be ignored in the same way. Needs preventative maintenance against corrosion in a marine environment.
 

vyv_cox

Well-known member
Joined
16 May 2001
Messages
25,351
Location
France, sailing Aegean Sea.
coxeng.co.uk
I'm not familiar with the design of your engine, but normally in joints such as you describe there is no contact between the bolts and the coolant. The bolts are usually surrounded by the gasket to prevent localised corrosion. If water gets to the bolt, the implication is that the joint worked loose, which sounds to be a logical explanation for your problem.
 

johnt

New member
Joined
30 May 2001
Messages
206
Visit site
and I go along with VYV and Howard on this one ...Im just a little suprised that VYV didnt jump on the helicoil thing as well!

Maybe she was just being ladylike :)
 

stevebirch2002

New member
Joined
11 Nov 2001
Messages
2,436
Location
k up your larder - Malvern & Portsmouth
www.albinvega.co.uk
I must agree with the other reply to this comment The so called "Friendly Engineer" is talking the proverbial "b***s"! Almost all new marine diesels are based on Japenese blocks. Helicoils are certainly not used in any of them that I know. I would suggest that standard preventative maintenance should be carried out by all competent boat owners on their inboard engines, whether the engine is one year or thirty years old. I changed my old Volvo MD6A for a Beta 13.5HP and I have not looked back. The difference is fantastic - smooth running, plenty of power, easy to install and spares are at a reasonable price. No I do not work for Beta just a very satisfied customer.
 

vyv_cox

Well-known member
Joined
16 May 2001
Messages
25,351
Location
France, sailing Aegean Sea.
coxeng.co.uk
My wife doesn't like me being ladylike.

In fact I have come across aluminium castings that are fitted with helicoils, or an insert very similar, in production. This is intended to avoid the very real likelihood that threads will be stripped by overtightening by enthusiastic maintainers. The alternative is to fit bolts and studs that have a very coarse pitch, contributing to the possibility that they will loosen themselves in service.
 

vyv_cox

Well-known member
Joined
16 May 2001
Messages
25,351
Location
France, sailing Aegean Sea.
coxeng.co.uk
I think that's what I said.

In my earlier post I said that there should be no contact between coolant and the stud/block threaded interface, regardless of whether there are helicoils or other inserts present.

So what's your point?
 

stevebirch2002

New member
Joined
11 Nov 2001
Messages
2,436
Location
k up your larder - Malvern & Portsmouth
www.albinvega.co.uk
Hi

I was just agreeing with you and trying to explain to "TADPOLE" that his engineer did not seem to know what he was saying. I have not got used to the forum reply system yet and was trying to explain to Tadpole. I agree totally with your comments on this subject.

Kind Regards

Steve birch

Albin Vega "Southern Comfort" V1703
 

Shanty

Member
Joined
20 Jan 2002
Messages
771
Location
Scotland - Black Isle
Visit site
I have a Beta 13hp about four years old. This winter, I discovered that there is a pencil anode in the heat exchanger. Mine had completely eroded away - How is yours? Lack of this anode could be allowing corrosion to take place. Beta Marine can supply replacements at reasonable cost.
 

tadpole

New member
Joined
2 Aug 2001
Messages
65
Location
West Dorset
Visit site
I'll check out the pencil anode, Tim, thanks for the tip. My engine bloke is a bit old-fashioned and probably not too au fait(?) with relatively recent diesel technology.
Steve
 
Top