john.k

Im only a newbie here,so I wont say all this is twaddle............have you ever seen or worked on diesels run on ordinary oil.....not that its possible to buy it any more.........When I was an apprentice,the head mechanic was "Old Tommy".......he was dark and swarthy and had jet black hair,and jet black fingernails.........when he retired ,the boss called him back to find some lost items .......I didnt recognize him........the voice yes......but here was a guy with whitish grey hair,and pale face and hands...........it was Tommy ,with the black washed/worn off.

Badly worn vanes in the transfer pump can cause issues with very low transfer pressure...so its probably wise to have the whole pump checked out......even if that doesnt cure the problem...I hope he checked the fine plastic mesh filter in the inlet nut.....a common cause of starvation.

I dont think that a fuel weep from the pump seal would possibly be responsible for the slowing of the motor.The leak must have been minor,a total seal failure quickly fills the entire motor with fuel and it runs out into the bilge. The way I see the motor slowing is if the shutoff gradually engages.The way the DPA is set up is that a solid link shuts the throttle valve,but it is only pulled open by a very weak spring.This is why the pumps are so easily affected by fuel fungus......the weak spring cant pull the valve open.,and the motor cant start.,,,,edit........unless the bearings were starting to run hot,but he says the coolant temp was low.

With a DPA pump you should always smell the dipstick to check for diesel in the oil........very common in Perks,but doesnt seem to do any damage.

I had repeated callouts to a problem like this,and after much tankflushing,filter changing ,etc,it was a piece of polyester shirt material ,invisible when fuel wet,and would stick to the inside of the tank,when the tank was drained and flushed.After a period of running,it would float over the pickup,and restrict fuel delivery......It could have been cured first off by placing a large filter gauze over the pickup pipe when the tank was made,or putting a decent sized manhole in the tank top.But boat operators dont like filter gauzes in tanks,because they block with sludge............Incidentally,if a DPA pump gets air in it ,it usually wont start,or stalls straight after starting......One cause of this can be the controll spindle O rings worn.

I dont see the connection between a paper element filter and not using multigrade?..Is this something I should be aware of.?.........Strange that operators who run engines for a couple of hours worry about all this,when pro s dont...We were running GMs on Valvoline Allfleet 15/40 ,with heads off at 10,000hrs,and pistons/ liners and valves at 20,000hrs,which was 1 yr and 2yr intervals...........despite all the dire warnings in manuals,the only measurable effect of the multigrade was a considerable saving in battery costs...............I might add I have a 4LW in a yard crane that hasnt had the oil changed in 20-30 years,and it still runs quietly,and starts straight away..The crane will rust away,before the Gardner quits.

OK,thats my point......if a bit breaks in a 3/152,you can buy another same day,instead of searching for six month.....and I dont see that a Coventry would be any different in the sound department.........all 4cyls sound like tractors........

I have a 3YC from a RB10 that I completely rebuilt with parts I got from GEC Diesels when they were closing,and tossing everything out.My only fault with them is the exposed governor/pump rack setup that is very prone to freezing up ,unless the motor is well protected from the weather.

OK,call it marine,...still an orphan,and no better than an anchor,unless you happen to have a shed full of spares............and the SCG is also an orphan........and probably the same issues with asbestos containing spares being dumped.........anything flexible from the last 100 years will likely have asbestos in it........its that versatile............and also produces a very nice income for eggheads and tossers in spacesuits.

Asbestos mania has killed most odd engines deader than they already were........out here its a crime to sell asbestos products,so all the NOS headgaskets have been dumped.........and solid copper gaskets are simply useless on the vast majority of diesels......but I cant understand why anyone with a hankering for old motors doesnt simply get a Perkins......I reckon a 3/152 would be ideal,or a 4/203 ....or a bit bigger a 4/236..............they are all from the sixties,and cheap spares are abundant..............no thousand quid heads cast in mud hut using yak dung.

Godiva are a manufacturer of fire pumps,sprinkler booster pumps,etc.......very costly gear with very fine clearances...............and for some reason they loved Coventry Engines,which no one else does...............Your motor has been salvaged from a fire fighting set,and the old SCG box added................how many orphans in one lot.?

Edit.........shaft bore diameter is 3.00",(might include some heavy grease.)...will sort out the rest..asap.

I have had a look at the bearings.......the army tag says......"Set,bearing,gear end ,inner and outer...2".........so its one flanged bearing .wt 10 lbs,...one plain bearing ,wt 8.1 lbs.......there are 5 sets of 2....nothing to get excited about.....Unfortunately ,there are no part numbers on the bearings that I can see....Other stuff will be all mixed up with years of engine bits.....the main bulk was the old head gaskets ,four big cartons full..............and asbestos is a big deal......if the council finds it.

i dont have a container full,and asbestos is getting to be super big deal here,and with council inspectors buzzing round,I have to be very careful....Had a laugh at the scrappies tho,I warned him the gaskets were asbestos,and not to put them thru the shredder,....So he says..No worries ....we will strip them in the "clean room"......the whole place is like the black hole of calcutta......and he grinned with 3 teeth.....orrible.

Martyn,they are the big full circle end bearings,and in undersizes,which means you need new timing gears,etc.I dont have any of the intermediate split ones........the head gaskets are asbestos,so I sold them to the scrappies ,and good riddance....I was always impressed by the JPs a kid ,screwing out the changeover valve with flame and smoke blasting out.