LR1 Won't start

[Avondale]

Hi

I bought an 'unfinished project' LR1 from a chap locally. The engine was in pretty bad shape, so I set about rebuilding it, thinking it would be straightforward !

Complete strip down, new piston and cylinder, de-coke, valves ground in, new gaskets. New fuel tank.

I reassembled it with the original fuel pump and injector, bled the fuel system but it will not start.

I know I am cranking it in the right direction. I have checked the fuel pump rack and set that according to manual. The decompression is set right.

The crankshaft and camshaft timing marks are aligned. Compression seems healthy.

I can hear the injector 'creak' but still no joy.

Where do I go from here? What should I check / adjust next?

Thanks

[AdeV]

Pull the injector out, re-connect it to the HP line, and crank the engine with the injector in free air (keep hands/eyes/small children/sandwiches well away - it can inject diesel under the skin if you're holding it, and it'll make your sandwiches taste terrible). It should give a nice mist when it creaks. If you get something more akin to a slug or jet, then you need to have the injector refurbished, or replace it.

Assuming the injector's OK, replace it; then drop "some" oil into the intake valve. Probably around 1/4 cup. Crank it like crazy and drop the decompression lever - hopefully it'll up the compression enough to fire it.

[cobbadog]

Excellent advise Adey. It is the best way to confirm that the injector is spraying a lovely light mist. I can also confirm that diesel on sandwiches is not a good thing.
I also read the list of replacement parts but no listing of new rings as well, hopefully these were done too.
Go back and bleed the fuel system again and do it one section at a time. Fuel tank to inlet of the filter bowl, bleed the bowl, then to the fuel pump inlet side then outlet side when cranking next at the injector inlet. Really ensure there is no air in the line.
Remember from the pump to the injector the amount of fuel that is pumped is just a dribble at best but when it has to make the injector open the pressure gets up over 1000 psi from memory and is the reason for keeping any part of you and your sandwich away from the nozzle. Don't be tempted to try and use anything to poke in the hole/s of the injector, this will destroy the tip immediately.
Using a quarter of a cup of oil down the inlet is a sure way to increase the compression to make them fire but if you have done the liner, piston, rings and head it should not be needed. As a last resort if you still have no joy use a small amount of either or start ya bastard down the air intake and see what happens. And I do mean a small amount. Once started let it run for a while varying the rev range to help bed the rings in.
Good luck and keep us posted as to how you get on.

[Avondale]

Thankyou for your advice Adey and Cobbadog

When removing the injector to test, should I use a new pipe, or bend the one that is fitted? I read somewhere that it could split if bent too much?

Thanks again

[mike90045]

Thankyou for your advice Adey and Cobbadog

When removing the injector to test, should I use a new pipe, or bend the one that is fitted? I read somewhere that it could split if bent too much?

Thanks again

I loosen both ends of the high pressure pipe, to move it around, and then retighten to test the spray pattern.  In my experience, if you are getting the creak (on my 6/1, its more like a Tingg) you are not likely to have air in the line.

[AdeV]

As Mike says, if you loosen both ends, you should be able to wiggle it about such that minimal bending is required. I can't remember what shape the LR1 pipe is, can you tighten the bottom up such that the top is in free air somewhere? If not, a little bending won't hurt, and you can always heat it if you want to be sure - just make sure at least one end is open to allow any expanding fuel/fire out!.

[guest23837]

You could try a hair dryer on high blowing into the inlet manifold let it heat the head a little too. Is there anything out of it smoke wise? does it make an attempt at firing? Sometimes engines that have been sitting take a while to get going again it's worth sticking with it.

[Avondale]

Thanks for the very useful advice.

In the end, I purchased a brand-new injector which is working well, but still 'no - start'. I get an occasional puff of smoke from the exhaust muffler, but nothing that resembles 'starting'

It makes me think I may have a timing issue. During the rebuild, I had the camshaft out to check it, but I was careful to align the crank/cam marks on reassembly.

I also took the fuel pump apart to check this, but again, (which was all OK) I was careful to align all the relevant marks. I put .036" shims under the fuel pump and set the rack up according to the manual.

Is there something I have missed re.timing?

Your help and advice as always is most appreciated

Peter

[AdeV]

Have a search for Spill Timing, that's something to do with the fuel pump. Can't help further, as I've never done it, but I'm sure that's for timing the injection pulse.

[sirpedrosa]

Hi Peter

You are struggling with that engine. A LR1 is supposed to be very straightforward.

If, and I remark if, everything is in place: turns freely, bump clearance set, time marks in place, IP spills ok at delivery valve, high pressure line ok, injector (needed new?? really?) spill ok (cleaned? squeaks? sprays?).

New fuel tank! Cap has the tiny hole to respiration?

So, it must run... unless it wants to take a ride to the witch.

Cheers
VP

[cobbadog]

Yeah sounds like a fuel timing issue and this too I have had no experience with. Like every other engine timing is everything. Out with the manual and read up up the spill timing. I did read this one time a long time back and it was a bit confusing as to what was what as they called parts by a different name than what I am used to. Some diesel engines have a spill timing mark on the flywheel and if this is the case this is where you start to check it.

[Avondale]

Hi there

I thought I would check my Bump Clearance and found that the lead wire (1.2mm solder) would not compress at all as per the manual.

During the rebuild, I fitted a new cylinder due to excessive wear of the old one.

I re-checked  the Bump Clearance using the old cylinder. To my surprise, the lead was compressed to 25 thou as per the manual!

So, I checked the length of the cylinders and found that there is a discrepancy.

The old cylinder is 149mm and the new one is 150.9mm - a difference of 1.9mm. The measurement was taken from the flat surface of the cylinder at both ends. (see pic of piston in new cylinder)

I haven't reassembled it again yet, but could this be a reason for my none-start?

Peter

[sirpedrosa]

Hi Peter

Maybe my thread give you some help, take a look: https://listerengine.com/smf/index.php?topic=8333.msg100281#msg100281

The important is the final clearence! but review again your time marks.

Cheers
VP

[cobbadog]

Well this would drop your compression down quite a bit. Very good thinking and find to identify the problem. As you know diesel engines reply on compression to fire and this would have dropped that by wuite a bit. Not sure what end should be machined to bring it back to specification. Does your manual give you the correct overall length for the cylinder? It would be somey=thing I feel that should be attended to.

[AdeV]

I haven't reassembled it again yet, but could this be a reason for my none-start?

Almost certainly - although it may not be the only reason, it's definitely a big factor.

Were there any shims under the old barrel? If so, you could remove them to reduce the height discrepancy. If not, then I can only surmise that either your piston is not original, or has been machined short. The only reason I can imagine your old barrel is so short is because it's previously been machined to fix a problem. I guess one other possibility - the conrod is shorter than standard.

Either way, assuming there's no shims to remove, the simplest solutions would be a) Machine the barrel down to match the original, or b) Acquire a marginally longer conrod. Or piston, if it looks like that's been machined.

Can you supply pictures and accurate measurements of the piston height & rod length? I have an LR1 buried at the back of my shed, which is mostly in bits.... I'm happy to do some measuring up if you like. Mine had "some" (2 or 3 as I recall) thin shims under the barrel, at a guess they'd add about 0.5 to 1mm height all in.

Cheers,
Ade.