Series 3 Bench Testing a 2.25 diesel

Friend has recently acquired a complete 2.25 5mb diesel to fit to his series one to replace the old Peugeot engine that has thrown all of its rods. The engine moves freely but has been sat on a pallet (garaged) for several years. Before fitting it we want to bench test it to try and gauge the condition to decide if it needs a full rebuild or just a good service. At this point we do not really want to spend any money on it until we have got it running as one option is to use it as an exchange for a recon unit rather than rebuild ourselves. We were going to check the oil level, spray some over the rockers, fit a pressure warning bulb and spin it over with no fuel to see if it build pressure. Were going to bleed the fuel sstem and then see if it will start. What would the recommended procedure be for starting up an engine which has sat for so long?

In terms of bench testing rather than fitting to a vehicle, we are planning on running a hose from a jerry can to the the lift pump and a return back to the jerry can. We are going to replace the glow plugs as I know how important these are to getting an old diesel to start, and were then going to use a set of jump leads straight to the starter. Does anyone have any better suggestions?

Compression test will tell you lots.

+1 on compression test, if its low it will be a pig to start and the head will have to come off anyway. Tester is only about £25 off e-bay but make sure you get one with the right adpators, I think the tractor kits have the imperial adaptors.

rob1miles said:

+1 on compression test, if its low it will be a pig to start and the head will have to come off anyway. Tester is only about £25 off e-bay but make sure you get one with the right adpators, I think the tractor kits have the imperial adaptors.

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Having not used a pressure tester before (although I have an old fashioned petrol one you just hold into the spark plug hole) What do I actually need, there seems to be lots of different ones available and I do not want to end up getting the wrong one.

Apart from spraying oil over the rockers, you should ensure some gets past the open valves and into the cylinders ( is that what you mean ) then turn the engine to ensure the new oil gets wiped around the cylinders. It's gonna be noisy when it fires up. I would bypass the lift pump by hanging a fuel container higher than the engine and let gravity do the work.

Col

Colthebrummie said:

Apart from spraying oil over the rockers, you should ensure some gets past the open valves and into the cylinders ( is that what you mean ) then turn the engine to ensure the new oil gets wiped around the cylinders. It's gonna be noisy when it fires up. I would bypass the lift pump by hanging a fuel container higher than the engine and let gravity do the work.

Col

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Yes that is what I meant, When we do the glow plugs will put some directly into the bores and turn over by hand to begin with.

What are the reasons for it being noisy on first start up (other than no exhaust) is that to do with oil circulation and it should settle once it is properly flowing and coated everything again?
As long as we can get it to run, even if noisy and smokey to begin with, we will probably fit is and see if it improves any with a good service and bit of use. If after some use it is still noisy and smokey will will then look at other options.

If it was my engine I would have the sump off, clean it out and look for metal particles and put new oil in before firing it up. Definitely not run it on years old sump oil.

Agreed, some new oil, just in case the sump has a load of water in, you could wreck a decent bottom end. Take the injectors out and motor it on the starter to get oil pressure, this is good with some oil down the bores, that also frees the rings and ups the compression a bit. If you go for a compression tester you need one with the "H" shape adaptor that clamps the test connection over the injector hole. I think I bought one like this:
https://www.ebay.co.uk/itm/New-17-p...h=item3d39edf065:g:ik8AAOSw1ZBUsMNc:rk:3:pf:0
It told me my engine needed a rebuild, I could probably have worked that out but I was in denial. Its the kind of thiing to buy with a few mates as it will get used once a decade but when you do need it nothing else will do.
Follow the CAV pump bleeding sequence, inlet, litle screw on the side, injector unions just cracked. The Perkins manual says tighten 2 and leave 2 cracked, this seems to work really well as its starts on 2 and you then tighten the other 2.

Be careful with spraying oil into diesel engine cylinders - if you put in too much and you are unlucky you could get a hydraulic lock which will bend things

(The common method of adding oil to a cylinder on a petrol engine to see if the leak comes more from the bottom end than the top can also work on a diesel but it really ought to be done with great care)

I personally would prefer to do a compression test on an engine on a pallet rather than rigging up some diesel and trying to get it to run. From what I have heard series diesel engines can be a real pig to try and get to run if they have been sitting for a while - stories of tow starting them for a few miles before you get a hiccup...

(Possibly internet bravado)

If it’s going for a rebuild just send it and let them do the testing. Many problems may not be apparent until stripped. A half decent diesel will run with all sorts wrong with it. That’s what they are good at.
No good doing any work on it until the engineers tell you the piston tops are goosed or the bores beyond salvage.

My five bearing has run well for three years but blows like a good en out of the oil filler. I wouldn’t be sure if it would be accepted for rebuild.

Bobsticle said:

If it’s going for a rebuild just send it and let them do the testing. Many problems may not be apparent until stripped. A half decent diesel will run with all sorts wrong with it. That’s what they are good at.
No good doing any work on it until the engineers tell you the piston tops are goosed or the bores beyond salvage.

My five bearing has run well for three years but blows like a good en out of the oil filler. I wouldn’t be sure if it would be accepted for rebuild.

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If it starts and run with no problems then it will not go for a rebuild. It will only get rebuilt if there is something wrong with it. If we can get it running nicely with a good service then we will save the money on an expensive exchange unit.

Its aways a bit of a gamble. If the bores and crank are good then you can fix most anything esle once its in place. That was what happend to me, I put in an engine with a good bottom end but damaged bores so while it ran it was unusable. I'd spent £120 on the engine and £600 getting it fitted, but I then had to rebuild it in the vehicle. The Perkins can be re-sleeved in situe so I rebuilt it where it was. The rebuild cost £250 and now its a really good engine (see the video on the Brookland military day). Would I have done things differntly, not easy to say. I don't have a workshop so rebuilding in the vehicle was no different to rebuilding it on the trailer where it was stored. I would probably have stripped it then fitted it as a bare engine as it would have been a lot lighter. I had to buy my engine with no history, the lesson for me was to spend more time finding out about why the engine was taken out. Piecing together I now know mine was rebuilt but they put new rings in old bores and they broke wen it was run so its was ripped out but all the new parts were left on. Knowing that i would have ordered the sleeves and not wasted time trying to get it to run well.

If I had an engine out I would inspect and rebuild the block as a matter of course before even attempting to start it.
As everything else is practically bolt on and easily sent out to be refurbished it could also be the cheapest option.
Even if the cylinders need relining it’s an Easier job to take the block to a local engineer. Chuck some crank bearings and seals in and a set of big end shells and your almost starting from new.
It will no doubt need a new timing chain anyway before attempting fine adjustment and by the time all that’s done the head could have been exchanged for a fancy refurbished one and be sat ready to be nailed on.
It will also mean you can check all the problem areas for wear that crop up continually on the forum.