Like for like swap of my Perkins 4108

A good few years ago ( about 12 I think) I had my 4108 rebuilt by a commercial garage on the outskirts of Cumbernauld that specialised in reconditioning bus and plant engines. Cost was £850 as I remember.
The Perkins dealer up the road wanted £1850 plus a ' possibly refundable' deposit of £850.

If I was replacing I'd definitely go with Beta. Good engines and great service.
 
wully1 said:
A good few years ago ( about 12 I think) I had my 4108 rebuilt by a commercial garage on the outskirts of Cumbernauld that specialised in reconditioning bus and plant engines. Cost was £850 as I remember.
The Perkins dealer up the road wanted £1850 plus a ' possibly refundable' deposit of £850.

If I was replacing I'd definitely go with Beta. Good engines and great service.
Click to expand...
You won't get much from Beta for £850!
 
Just a thought, if you are up to spanner work you could do the complete rebuild yourself as the 4.108 has liners so you dont need to get the block rebored. Cost for parts as follows.
Engine block kit inc pistons liners gasket
£350
Valve train assembly £70
Camshaft £85
Rocker arms £160
Top gasket set £50
Oil pump £160
And so on so call it £1000 + VAT but you may need crankshaft reground which will add a bit to the cost.

Although most of the work is straightforward, removing the liners is a bit of a fight as you need to use a bit of force to remove them. One method being to run a beed of weld down the centre of each liner which causes the liner to contract. To be honest I would think about getting an engine shop to pull the old liners and refit the new ones.

Go on YouTube or talk to Skipper Stu of this parish.
 
Jcorstorphine said:
Just a thought, if you are up to spanner work you could do the complete rebuild yourself as the 4.108 has liners so you dont need to get the block rebored. Cost for parts as follows.
Engine block kit inc pistons liners gasket
£350
Valve train assembly £70
Camshaft £85
Rocker arms £160
Top gasket set £50
Oil pump £160
And so on so call it £1000 + VAT but you may need crankshaft reground which will add a bit to the cost.

Although most of the work is straightforward, removing the liners is a bit of a fight as you need to use a bit of force to remove them. One method being to run a beed of weld down the centre of each liner which causes the liner to contract. To be honest I would think about getting an engine shop to pull the old liners and refit the new ones.

Go on YouTube or talk to Skipper Stu of this parish.
Click to expand...

As per previous, thse guys know their stuff, really going for it and prices are right.
Stu
 
DownWest said:
Couple of years ago, I sorted some probs on a 4-108, that came from a Challenger(?) tank. Low hours and in good nick. Replaced the seized old 4-108 that had sea water up the exhaust. The sorting included a new water trap to avoid the fate of the previous engine.
There is an outfit that supplies such engines. Ex lifeboats and other commercial users.
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There are a couple of sources of low hours ex-MoD Perkins 4108s. Here is one of them. http://www.armyuk.co.uk/equip.php?ID=688
 
.
just yesterday I helped bleed and start a neighbour's 4108 after sitting idle for two years. After bleeding it started easily and sounded good. He took a video of it. The main reason he's considering a change is that he hates an oily bilge, but on top of that he's now planning towards long duration offshore cruising and then also wants hydraulic drive for a bow thruster. He also had an marine engineer give it a once over and has that report - saying that it's a good engine (aside from the usual felt seal leak). The point (pertinent to this thread) is that it may be for sale and if you're quick - it can be seen and heard running. PM me if interested and I'll reply with his mobile number.

Pete.
 
30sqm said:
.
just yesterday I helped bleed and start a neighbour's 4108 after sitting idle for two years. After bleeding it started easily and sounded good. He took a video of it. The main reason he's considering a change is that he hates an oily bilge, but on top of that he's now planning towards long duration offshore cruising and then also wants hydraulic drive for a bow thruster. He also had an marine engineer give it a once over and has that report - saying that it's a good engine (aside from the usual felt seal leak). The point (pertinent to this thread) is that it may be for sale and if you're quick - it can be seen and heard running. PM me if interested and I'll reply with his mobile number. Pete.
Click to expand...

I'm new to using this website and hadn't realised that there are no PM's, so you'll have to text me on UK : zero-79-five-8, one hundred, 633. Cheers,
Pete.
 
Tranona said:
Well, you have answered your own question. Buy an old motor - plenty around, have it reconditioned - plenty of people still able to do this. Makes sure that it is compatible with the way your engine is marinised and fit it. Would guess the reconditioning cost is likely to be in the region of £2500-3000, that is between 60-70% of the cost of a new engine, plus your core engine cost. These things have a habit of being a bit open ended until you have a known core from which to work. So, likely to be a bit cheaper than a new engine - but unless you find a core that needs little work - not much.
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I did the exercise in 2009, between re-conditioning a 2GM20 and replacing it with a new 3YM20.
Reconditioning costs involved new main and big end bearings, crank regrind, rebore and os pistons, a new oil pump, valves and seats. when within £80 of the new engine I gave up, with a 15 year old box and possible cam regrind still pending.
Specialist work done by others but stripping and assembly by myself.
Bearing in mind I was considering a twin, not a 4-cylinder for refurbishment costs, and that I already had the engine....
I'd be very surprised if the OP didn't find similar costings but appreciate that having made up his mind he doesn't want to be confused by facts.
 
Don't confuse Yanmar rip-off prices with part for a Perkins. Some examples below for single cylinder Yanmar, compared to four cylinder 4.108

Yanmar main bearings £64 Perkins £16.25
Yanmar valves (two, just the valves) £52 Perkins kit, 4 valves, springs, guides, seals £67.50
Yanmar head gasket £26 Perkins £16
Yanmar piston rings £72 Perkins £41

Etc

So it can actually cost more to rebuild a single cylinder Yanmar than a four cylinder Perkins. Compare that with the cost of a new engine, Yanmar 1GM10 £3800 or double that for even the cheapest replacement for the 4.108.

Fitting costs should not be underestimated for either case. In some circumstances it can cost a few £k to fit, engine beds to re-make, new fuel/water/exhaust systems, new stern tubes, prop shafts, props are all possible.
 
Flica said:
I did the exercise in 2009, between re-conditioning a 2GM20 and replacing it with a new 3YM20.
Reconditioning costs involved new main and big end bearings, crank regrind, rebore and os pistons, a new oil pump, valves and seats. when within £80 of the new engine I gave up, with a 15 year old box and possible cam regrind still pending.
Specialist work done by others but stripping and assembly by myself.
Bearing in mind I was considering a twin, not a 4-cylinder for refurbishment costs, and that I already had the engine....
I'd be very surprised if the OP didn't find similar costings but appreciate that having made up his mind he doesn't want to be confused by facts.
Click to expand...
I have looked at a lot of ' facts ' and opinions quoted as facts! Whilst you do quote what I have to accept as facts your situation was probably quite different in other respects. Objectivity is one thing but there is no need to be rude!
 
pcatterall said:
I have looked at a lot of ' facts ' and opinions quoted as facts! Whilst you do quote what I have to accept as facts your situation was probably quite different in other respects. Objectivity is one thing but there is no need to be rude!
Click to expand...
Bottom line Pete, cheaoer to rebuild plus really and truly, if it is running ok, burning a bit of oil perhaps, it will still last for years!
Stu
 
FWIW our local mechanics told us that the Lombardini was a straight slot-in to a Perkins set-up, that it was cheaper and that they had found reliability similar to other brands.
 
PaulRainbow said:
Don't confuse Yanmar rip-off prices with part for a Perkins. Some examples below for single cylinder Yanmar, compared to four cylinder 4.108

Yanmar main bearings £64 Perkins £16.25
Yanmar valves (two, just the valves) £52 Perkins kit, 4 valves, springs, guides, seals £67.50
Yanmar head gasket £26 Perkins £16
Yanmar piston rings £72 Perkins £41

Etc

So it can actually cost more to rebuild a single cylinder Yanmar than a four cylinder Perkins. Compare that with the cost of a new engine, Yanmar 1GM10 £3800 or double that for even the cheapest replacement for the 4.108.

Fitting costs should not be underestimated for either case. In some circumstances it can cost a few £k to fit, engine beds to re-make, new fuel/water/exhaust systems, new stern tubes, prop shafts, props are all possible.
Click to expand...

I fear you are missing the point - I was comparing like with like, Yanmar with Yanmar, not a Yanmar with a Perkins 108.
The OP's alternative to completely rebuilding the Perkins is to buy new a marinised Kubota.
That I am prepared to bet, if it's not a partial recondition, will be a cheaper alternative.
Of course a top-end overhaul of the Perkins would be the cheapest alternative of all.
 
Flica said:
I fear you are missing the point - I was comparing like with like, Yanmar with Yanmar, not a Yanmar with a Perkins 108.
Click to expand...

No, i get the point, but it's not relevant to the OPs question. He has a 4.108, so your Yanmar comparison is irrelevant to him. If he is to make a comparison it has to be between rebuilding his Perkins or replacing it with a new equivalent, that's the question he's asking.

The OP's alternative to completely rebuilding the Perkins is to buy new a marinised Kubota.
That I am prepared to bet, if it's not a partial recondition, will be a cheaper alternative.
Of course a top-end overhaul of the Perkins would be the cheapest alternative of all.
Click to expand...

That's a bet you would lose i'm afraid. If you price the parts up to rebuild the Perkins the bill comes to substantially less than a new, comparative, engine. Don't forget also that the cost of removal and refitting the Perkins has to be discounted, as there is a remove/refit cost with a replacement engine. You can also discount a certain amount of the labour for a rebuild, as there will also be a labour cost for converting the current installation.

That said, i've just removed and stripped a 40 year old Yanmar that has been sitting on the hard for 10 years. This thing is in remarkable condition internally. Other than some cylinder pitting, due to minor water ingress due to a faulty cylinder head, there is little wrong with the engine. There is negligible wear on all of the moving parts and to effect a reliable rebuilt will cost substantially less than a new engine. I'm currently evaluating options to effect the repair and will start a thread with pictures and details of the work in due course.
 
I've just rebuilt my 4.108 in a similar Neptunian. One of the few weaknesses on the base engine is a tendency to crack between the valve seats. That's what had happened to mine, but even after finding a new replacement cylinder head, the total rebuild cost including all the machining, was still less than £1500. Good value, but actually it's sourcing replacement parts on the marinised cooling system that is more difficult.

Another consideration,is that, although the engine can be readily overhauled, that still leaves the raw water cooled, TMP gearbox to worry about. Even though all the parts are available, they are very expensive and the box is complex to work on.

Uncertainty with the longterm future of the box would tip me towards looking at a replacement, but then there is the issue of engine beds. The Neptunian has two transverse beds at the extreme front and back of a very long engine / gearbox combination. A replacement Beta 4 cylinder 38hp (?) is much smaller and would need significant and creative engine bed work to mount it, especially as it needs to go quite low in the boat to match the horizontal propellor shaft.

A decision to replace or not is actually quite complex and the cost of Yanmar spares would seem to be the least of the OP's worries.
 
Thanks all.
Yes, the actually engine is only part of the story. The comments from motor sailor are very relevant. Our engine is mounted at the rear of the TMP with just one central mounting. We have a spare TMP box. Our engine is still working well but we are accumulating spares like heat exchangers, pumps, starter motor, overhauling them so that we know we can have the engine rebuilt and have the reconditioned parts ready to fit.
It also ' feels good' to be refurbishing rather than throwing stuff away!!
 
"It also ' feels good' to be refurbishing rather than throwing stuff away!!"
I'm with you on this Peter. Also by refurbishing before you need them, you'll never be hunting around frantically if you have to replace.
I understand your Perkins is robust and economical so it makes sense to keep it going.
 
There was a guy selling army surplus 4-108's a week or two ago. 200 hrs ( barely run in ) dry stored £1500 for a motor.

I am going through the whole same issue at the moment.

Finally decided on a Beta 38 as 'drop in' a replacement. It awaits shipping to Greece in my garage. Based on the Kubota industrial engines spares are available worldwide. In addition it weighs about 80 kg less than the perk, is slightly more fuel efficient and is considerably more compact than the perk. It is also compatible with my current Kiwiprop setup, exhaust silencer, water trap etc etc.

The 4-108 only gets 50 hp at 4000 rpm, the Beta gets 38 at 2600. I never ran the Perk at over 2200 rpm ( it has 7000 hours plus on it and I was scared it would detonate! :) ) at which point the perk was delivering about 35hp so it looks very very similar if I max out the Beta at 2500 or so.

Another attraction is that the Beta runs on modern 'motor car' oil wheras the old perk needed some more expensive muck ( of which I still have a 20l drum!!!! )
 
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