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Author Topic: AB1 pistons and rings- compatibility. Where to buy.  (Read 3440 times)

Tim2

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AB1 pistons and rings- compatibility. Where to buy.
« on: December 30, 2018, 08:18:18 PM »
Hello to the group,

I’ve just joined up after searching the net for some info and on an AB1 that I have brought back to life and finding it all here.  This site has been a wealth of information and has helped me from get it up and running, although I do have a couple of problems to sort out.

The engine I have was having starting issues and very hard to start. After a injector service and pump rebuild (Brice pump that we accidentally damaged from the filter disintegrating and clogging it up) it improved the situation but not completely.  I suspected low compression and this was proven when two primers full of oil would get it going right off the second turn over (we fitted a starter motor) or plenty of aero start would get it going.  Once going it has no rattles or bearing noises, I’d say it’s in good nick.

But the barrel...  my suspicions were confirmed when I stripped it down, the barrel was completely glazed and had water pitting, after a deglazing hone its still on specification for its STD size piston.

My piston and rings almost looked new, in fact the piston had a very thin layer of carbon on top and still had all its machining marks on most of the skirt, the rings also looked to be halfway through their life and the end gap was just under a mm in the freshly honed bore, then I snapped the second ring re-fitting it.... must have been brittle.

I’m looking for a new set of rings. This engine is a late serial number engine (later than 29189) but  has the early non spring backed oil control ringset fitted. Is there a difference in pistons from early to late serial number or can you use either set of rings on these? (as the pistons are all the same and the newer spring backed oil ring is just better)

Does anyone in the group have some rings for sale or a 1st oversized piston and rings kit to sell or  maybe a good link to a seller.

There may be a chance, in the past somebody had to make do and put in what they had on hand in to get it going without a home and hence why the rings were looking fairly new but didn’t bed in and the bore is still in std specification after a hone, Will the info on the piston crown help out.

I’m based in Australia, this engine was rescued from an outback rubbish dump.

Cheers for any help,

Tim








ajaffa1

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Re: AB1 pistons and rings- compatibility. Where to buy.
« Reply #1 on: December 30, 2018, 11:21:01 PM »
Hi Tim and welcome to the forum. Sorry to read that you broke a ring. Any engineering shop that rebuilds engines should be able to source replacements and will probably charge a kings ransom for them.

I would recommend contacting Gary (aka dieselgman) at Diesel Electric Services in the USA. He holds the largest inventory of Lister, Petter  and other diesel parts in the northern hemisphere. He is very knowledgeable, his prices are reasonable and he has sent stuff to me in Australia before.

Bob

listard-jp2

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Re: AB1 pistons and rings- compatibility. Where to buy.
« Reply #2 on: December 31, 2018, 02:12:30 AM »
Since the AB and AC range share the same bore size (3"), you could just go on ebay and buy a set of these:

https://www.ebay.co.uk/itm/Piston-Ring-Set-for-PETTER-AC-Engine-76-2mm-3-0/401646331814

However before you do, make sure these rings are intended for the earlier indirect injection AC engine, as the later direct injection AC piston rings are slightly different dimensions.

Tim2

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Re: AB1 pistons and rings- compatibility. Where to buy.
« Reply #3 on: December 31, 2018, 11:27:19 AM »
Thanks for the advice to contact dieselgman I’ll definitely contact him.  I have been looking at a couple of ring sets on eBay, but will hold off until I find out a little more info as rings are fairly common although pistons are not and at some point I’ll need a spare.
  Once this engine is running properly and I know the bottom end is 100% I’m going to be keen to have a spare is piston and rings to go in. I guess what I need to do is find a parts calalogue for the A series engines and look at the part numbers across the range, this will answer everything, is there one available?
 My understanding is that all the 3” bore indirect injection engines use a flat top piston like my AB1, what I’m interested in is if they all use the same piston model and the later ring set is backward compatible and just an upgrade or what is the physical difference between both types? thicknesses, ring style etc. 

Tim

guest23837

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Re: AB1 pistons and rings- compatibility. Where to buy.
« Reply #4 on: December 31, 2018, 01:01:37 PM »
Google Jim Perkins in England he's a Petter expert good man for parts and advice and he's a nice guy as well.

http://www.petterengines.co.uk/

Willw

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Re: AB1 pistons and rings- compatibility. Where to buy.
« Reply #5 on: January 01, 2019, 04:26:23 AM »
Hi Tim2, welcome to the forum.
The newer AC1 piston ring sets that I have seen use a thinner top ring than the older style ring sets.
The 2nd ring and the oil scraper ring worked on the old style AC1 piston that I was repairing.

According to this site the AB1 and AC1 use the same piston number. http://lister-petter.com/s/parts-spares/1/piston-assemblies

On several occasions in the past I have purchased piston rings from the Ebay vendor mentioned by Listard-JP2 with good results.

Good luck with your project.
Daily driver '97 GMC W4 tipper on WVO/Kerosene mix.
6/1 clone standby generator.
Too many projects.

Tim2

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Re: AB1 pistons and rings- compatibility. Where to buy.
« Reply #6 on: January 01, 2019, 09:22:56 AM »
Ahh, that’s great site to look at part numbers,

After getting back to the workshop this afternoon, I checked all of the numbers on the engine, and I had a typo on the engine number, with a bit of forensic work it turns out the 88313 on the corroded engine plate actually was 38313 so it’s an early type engine, this explains all, cheers for all the good advice and I’ll get on with ordering a set of rings and put it back together.

I’ll post an update as to how it performs once it’s back together,

Thanks

Tim