Tired old diesel - Help!

Alpha22

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I have an old Freeman 30 with twin Bedford 330 diesels on Parsons HG4 gearboxes. They were listed as 98 hp when new.

They start and run OK and shove the boat along at about 10 knots.

I see from the original spec and adverts for similar boats that something close to 20 knots is the norm. I apprecieate my engines are old, but is there anything obvious that could be slowing me down.

They rev well over 2500 when out of gear, but max throttle in gear will only just make 2500 rpm.

Bottom is clean, they make a bit of smoke on first opening up, but that clears to a haze once running. I think the props are 17x11 if that helps.
 
Bedford 330s in good fettle always ran clean. First and easiest thing to check is that the line on the inj pump flange is aligned with the line on the coupler housing.

Apart from that, it's down to aligning the flywheel injection timing marks to the marks under the timing inspection cover on the side of the pump.

I always found the 330 to be an excellent, if oily motor. In trucks anyway.
 
My injector pump is a bit different from the ones I have seen on road vehicles.
It is an inline, rather than a radial. If that makes a difference.
1yahwc.jpg
 
If it not broken dont fix it...

Latestarter will be along in a mo, he'll know more about them.

I reckon if they run ok hang onto them and save the ££ for when they need replacing.
 
got to agree with paulg.
knew a bloke with a freeman 33 twin v8 cummins diesel's(around 180hp each)
boat did 18knots tops.
theirs a freeman 41 on the same yard as me twin v10 twin turbo diesel's(around400hp each)only does high twenty's.
 
My injector pump is a bit different from the ones I have seen on road vehicles.
It is an inline, rather than a radial. If that makes a difference.
1yahwc.jpg

Yes that is radically different from stock road going motors and could account for the hazy exhaust.

Did my apprenticeship on Bedfords at a main dealer and motors as far back as late 60s I ever came across all had CAV DPA pumps.

Weird. Even the oil filter canister has been moved.

As someone mentioned, Latestarter will be along soon to tell you that that particular motor with that pump was used in a 1966, Indian made ditch pump, rotovator and combine harvester combo that did standby on weekends as the village generating set. :D

Still a damn fine motor in my book, only beaten by the Bedford 6 cyl 300 petrol from the RL. Now that was a good un.
 
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If it not broken dont fix it...

Latestarter will be along in a mo, he'll know more about them.

I reckon if they run ok hang onto them and save the ££ for when they need replacing.

Saw the thread and thought sick of talking about diesel fuel, was temped to take a look and saw Tinkicker had beaten me to it! He shows his age as well.

CAV Minimec mmmmmmm thats old, old, 330 went from a Minimec to CAV DPA rotary and back to Minimec on low blow turbo version.

Concur totally with Tinkicker and others, well they did beat me to this one.
 
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Saw the thread and thought sick of talking about diesel fuel, was temped to take a look and saw Tinkicker had beaten me to it! He shows his age as well.

CAV Minimec mmmmmmm thats old, old, 330 went from a Minimec to CAV DPA rotary and back to Minimec on low blow turbo version.

Concur totally with Tinkicker and others, well they did beat me to this one.

Never mind. If someone posts a thread to say they have a brace of sick Bedford 466's, I'll leave it for you to tell em the bad news. :D

Oh and to the OP, if you come across some new, old stock cam followers, buy em. You'll be needing em. Luckily they only take minutes to change, oh and and keep an eye out for the infamous rocker shaft oil feed pipe and clip.
The only real vices this motor had.
Very high mileage motors also suffered from worn bypass valve plungers and springs, so if your oil pressure starts dropping, usually a new plunger kit would sort it.


EDIT

Cam followers, am I thinking of 466 and 500 followers LS? Were the 330 followers the better, solid "mushroom" type that needed the cam removed to be replaced?

Can't quite remember. :o

But if they are the solid ones, its good news for the OP.
 
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Many thanks for your knowledge gentlemen.

So, the tinker on the south coast advertising 25 knots on original Bedford 330's could be stretching the truth a bit.... well a lot, possibly.

The max speed has never changed for me, possibly improved slightly after giving it a good blast.

The oil filter is plumbed directly into the tube-stack cooling manifold that runs across the front of the engine. I guess thats why it was relocated.

Can you tell me more about the rocker oil feed????? Where will I find it?

Many thanks again.
 
Many thanks for your knowledge gentlemen.

So, the tinker on the south coast advertising 25 knots on original Bedford 330's could be stretching the truth a bit.... well a lot, possibly.

The max speed has never changed for me, possibly improved slightly after giving it a good blast.

The oil filter is plumbed directly into the tube-stack cooling manifold that runs across the front of the engine. I guess thats why it was relocated.

Can you tell me more about the rocker oil feed????? Where will I find it?

Many thanks again.

Take rocker cover off. Oil feed pipe is to the front of the motor and is a push fit into an oil drilling in the head. It has a nipple that push fits into a hole in the rocker shaft and held in place by a sping steel clip around the shaft.

The clip has been known (often) to weaken or fall off if not fitted correctly, the pipe falls off or leaks oil, causing the rocker shaft and rocker arm bushings to wear rapidly. With engine running, there should be a healthy amount of oil oozing from the bleed drillings in the top of each rocker arm.
 
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Simple mushroom tappets on 330. 466, of POS!

On a serious note mainisation was actally good quality and done in house at the Bedford plant and marketed as a GM motor. Manifolds/coolers were from Bowman.

How heavy is your Freeman 8 tonnes? Running the ###'s I would guess at this weight you should get nearer 14 knots, WOT 25 knots they were on drugs!

I was still in regular contact with Stan O'Flynn Bedfords final chief engine designer until a just a couple of years ago. Stan will tell you 330 was developed with a proper GM big $$ budget, 466 and 500 done on a shoe string. 330 was capable of much further development, however British MOD wanted more cubes to get more power and no turbo, wrong! High blow 330 was the way to go, Stan was only permitted to do a low blow engine which never worked well. Remember as late as 1976 Bedford was still the worlds largest commercial vehicle producer, and Leyland was #2. How the mighty have fallen.

Cosset the old ladies and they will never let you down. Change them out, and you wil find they have heathy export value.
 
You need to approach the problem in a different way. Forget initially thinking about the pump. You need to think about the engine and without sufficient information you are working blind. First thing to do is have the compressions checked and without this information you dont know whats what. When these engines were first made perhaps in the early 50's It was common practice for people to take their car to a garage that was a "Hepolite Piston Ring" specialist (In the 60's I was one) and piston rings were not made to the high standard as today and were designed to wear instead of wearing the cylinder bores, anyway if all your compressions are good I would then turn to the pump. I would approach firm of Diesel Engineers who specialise in pumps. I would buy a re-conditioned one and have it fitted then send your old one off for re-conditioning, and when you get it back fit it on the other engine, so you end up with a spare.
I would also (and nobody seems to do it thesedays) clean up the inside of your engine by, warm the engine/s up and drain, fill with flushing oil, run at tickover for half an hour, drain and refill with flushing oil again, for another half hour, then fill with normal oil and filter change. You will be surprised how much gunge is still coming out in the second flush. You may also benifit from having the injectors checked.
 
be carefull with flushing oil's in older engine's.
the gunge can end up blocking internal's..
i only use flushing oil's in engines that have had a sump drop and clean or a rebuild.
 
Dear oh dear, how things get blown out of proportion on forums.

Mate, do yourself a favour and just enjoy the boat. Unless you can get the boat to plane, which is simply not possible with your current engines, you are restricted to displacement speeds. 10 knots is a good displacement speed for your boat, be happy with it.
 
be carefull with flushing oil's in older engine's.
the gunge can end up blocking internal's..
i only use flushing oil's in engines that have had a sump drop and clean or a rebuild.

Kind of agree, but a little stronger, there is no place for flushing oil in any diesel engine.

Likewise compression testing was never normally recognised at Beford's just like majority of diesel engine manufacturers. No published numbers, no point. Blow by test is the correct way. Messing with old motors without experience is unrewarding. Question for Tinkicker, how many corks 'should' you be able to drive up in the rear crank oil seal and how many has he ever actually managed to graunch in?

As to screwing with the old Minimec pumps, unless you have a problem leave well alone. Pump shops have a dyslexia problem, they cannot say the words 'no fault found'. You probably stand more chance of being struck by lightning than find an old pump of the correct spec, as to Delpi still having correct test plan on record...............

Repeat, Cosset the old ladies and they will never let you down. Change them out, and you will find they have heathy export value.
 
Kind of agree, but a little stronger, there is no place for flushing oil in any diesel engine.

Likewise compression testing was never normally recognised at Beford's just like majority of diesel engine manufacturers. No published numbers, no point. Blow by test is the correct way. Messing with old motors without experience is unrewarding. Question for Tinkicker, how many corks 'should' you be able to drive up in the rear crank oil seal and how many has he ever actually managed to graunch in?

As to screwing with the old Minimec pumps, unless you have a problem leave well alone. Pump shops have a dyslexia problem, they cannot say the words 'no fault found'. You probably stand more chance of being struck by lightning than find an old pump of the correct spec, as to Delpi still having correct test plan on record...............

Repeat, Cosset the old ladies and they will never let you down. Change them out, and you will find they have heathy export value.

God God, last time I set eyes on one was in 1983.

Only cork or wood things I remember in rear seals were the bits of wood in a Rolls Eagle rear seal housing.

I remember various bits of felt, string, graphited braid and wellseal in the Bedford rear seals.

Think the 500s had the graphited braid cut off about 25 thou proud of both sides of the seal housing for "nip" and wellseal dipped bits of felt rammed down the housing sides with a specially ground old screwdriver and hammer.

Also seem to remember bits of felt rammed down the rear seal of (maybe 330) with the knife edge oil thrower in the next channel.

I fear too many engines of different types since and too many brain cells have been lost to enthusiastic beer guzzling in the ensuing decades to remember with any clarity.

I have 18 in mind for some reason.
 
See my memory is corroded, thinking 466, which had four cork seals either side, they will NOT all go in even though manual said they must! 330 was different, must have had felts.

Point I was trying to make with these old engines, it is all about experience. Unless you have a tame Tinkicker you can access, leave to rust in peace.
 
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