1989 2.5td rebuild

[SanDiego110]

Hi all

My friend left for a deployment and left me with his smoky defender 110. I'm trying to fix it before he returns in April.

There is compression in the crankcase and white smoke everywhere. I pulled the manifolds and oil poured out of the intake. There was a big crack in the head gasket letting oil into the #3 cylinder, which I assume is causing smoke. 

So I'm cleaning up the head, relapping the valves and replacing the head gasket. I have new pistons and bearings, but now I'm not sure it needs them. How can I tell if the pistons need replacement without pulling them out? If they should be replaced, can I do it without pulling the engine out? 

Thanks!

Jeff

[monkie]

Hi, welcome to the forum.

I rebuilt one of these engines 18 months ago and put the write up on here, but photobucket went wrong and the pictures are gone - I'll fix it. These enignes have a bad reputation that is well documented if you google 19J engine. The early ones were a disaster but land rover made improvements in the late 1980's and it is these improved ones that are left running today.

What tends to happen is these engines crack pistons, this raises crank pressure, pushes oil out of the breather, soaks the airfilter until they run to destruction on their own oil if left to it.

With the pistons still in situ, you can only really inspect the crowns. Clean them up and look very carefully for cracks, they could be just hairline when cold. Also pay close attention to the head, they can crack between the valves where the metal is thinest. The combustion chambers in the head also crack.

 

[SanDiego110]

If and when you fix your write up, let me know, it would be very helpful.

I couldn't find any cracks on the piston crowns or the head, so I'm going to put it back together without replacing pistons and see what happens. 

[Snagger]

They crack the pistons and the heads, and the hot spots can sometimes drop out.  All in all, they're not a good engine - a Tdi is far more robust, powerful and frugal, so few will repair one of these.  Since you have already embarked on it, though, the crank shells should definitely be replaced as you have them, and if you've already got the head off and are undoing the big ends for the bearings, then it's little extra effort to replace the pistons.  

In all honesty, it's unlikely a 19J will have achieved enough mileage for significant bore wear, so a rebore is highly unlikely to be needed.  A hone might be needed if the bores are polished or glazed.  Piston damage is likely, but only fit genuine AE or Heppolite pistons (and rings); don't bother with pattern parts.

[monkie]

As Snagger says about bore wear, I was quite surprised to measure almost no wear in the bores on mine during the rebuild so I just honed them. At the time I couldn't obtain standard size AE pistons so I had to use pattern parts - if they fail prematurely I will just have to take it on the chin. Just make sure that they are for the 19J and not the 12J. (The 19J pistons have a teflon surface to cope with the stress of turbo charging). I'm not sure if the AE pistons for this engine are readily available. Also make sure you use the Elring composit head gasket rather than the metal laminated one.

You can probably tell (given I threw money into rebuilding one) that I am in the minority here and I am a fan of the 19J.

It's a fact that the Tdi is a better designed, more efficient engine; but it should it be as it a more modern design. The 2.5 DT (19J) was last in a series of developments of Land Rover's indirect injection diesels and is essentially a 2.5NA (12J) with a turbo (no intercooler) added. The original ones didn't take the stress of having a turbo very well, they craked pistons, heads and blocks, plus the primative crankcase breathing system was not sufficient (oil would be pushed into the air intake, destroying the engine) forcing Land Rover to  sort it out as the Tdi (in development) was a while from being in production. Land Rover modified the block, pistons, valves and breather system to improve the problems.

19J engines left in use now should be of the improved design with the older ones being taken out a few years ago now as failed units. In my view these later engines (as yours seems to be) are worth repairing if you like originality, it would be a shame to see them all ripped out and replaced with an ex-discovery lump. I also like my cab being quieter than when a Tdi was hammering away on a cold morning! If however I wanted a Land Rover for more than just pottering about in and used it for work - I would choose one with a more modern engine. Then again I would probably just have a transit van, but where's the fun in that?

[monkie]

Part numbers:

Standard size piston with rings - ETC8670

Elring head gasket - ERR3618

I would also recommend getting a set of recon injectors to help keep it running sweet as bad combustion from dirty injectors can contribute to cracking pistons.

http://www.paddockspares.com/564332r-injector-recon-late-sold-on-an-exchange-basis-price-includes-12-50-gbpexc-vat-surcharge.html

[SanDiego110]

So I should replace the pistons even though they look fine? I think the head gasket is the only problem.

Edited January 9, 2018 by SanDiego110

[SanDiego110]

[Snagger]

6 hours ago, SanDiego110 said:

So I should replace the pistons even though they look fine? I think the head gasket is the only problem.

Not if they are OK, but you'll need to clean them up and have a very close look for cracks, particularly hairline cracks. But, if they're not cracked, then you'll be in a very rare position.  I bought a 12J from a fire damaged vehicle for rebuild, but came across a cheap Tdi before I did the 19J.  I pulled the head out of curiosity and found each piston cracked clear across the crowns, wide enough to see daylight through the cracks, and that is pretty typical with one of these if it's burning oil.

That head gasket failure is heading towards a valve push rod bore, which also acts as an oil drain.  It could have been sucking oil into the bore on the induction stroke, but that's unlikely.  Almost certainly, the compression and combustion strokes resulted in gasses being pumped into the push rod bore and thus the cam gallery and block, pressurising the block and causing heavy breathing with a lot of oil mist, and that'd be the source of the oil being burned.  Happily, these engines have cast iron heads that are more resistant to gas erosion than the alloy heads of Tdis, so it should respond well to a skim, but check for cracks between the valve seats.  Again, these heads are more tolerant than the Tdis', and cracks are more reparable.  It's pretty normal for the pre-combustion chambers to have cracks emanating from their squared corners; don't worry about those unless they are more than half way to the edge of the outer diameter of the chamber piece or unless the chamber is loose in the head.

[monkie]

Here is a picture of one of my pistons that had a hairline crack in it, you have to look closely. It is down the middle starting just to the right of the tip of the V-shaped mark in the crown. The other picture is of a crack between the valve seats which is a common place for these heads to crack.

To add to Snagger's post and to underline a comment I made in a previous post, I would strongly recommend replacing the injectors for reconditioned ones then give it a good service changing the oil and filters. These engines do not cope well with neglect interms of infrequent oil changes. Hot spots arising from none uniform combustion caused by dirty/worn injectors can cause the problem of cracked heads and pistons.

 

[Landrovernuts]

It would be interesting to know how well the 19J would last if it was fitted with a charge air cooler - not for extra go, but to drop the temperatures. May be piston life would be extended and cracking may well be reduced. 

I remember many moons ago someone fitting a 200tdi rad and intercooler set up to a 90 with a 19J and it fitted really easy with little modification work. I recall hearing good reports but nothing on if it made it last any longer. 

Toby

[monkie]

1 hour ago, Landrovernuts said:

It would be interesting to know how well the 19J would last if it was fitted with a charge air cooler - not for extra go, but to drop the temperatures. May be piston life would be extended and cracking may well be reduced. 

It would be intereting to hear about it to see if it does help in the real world on a 19J - I remain to be convinced that an intercooler would make a significant difference in this case.

However I think regular servicing and sympathetic driving go along way to get more life out of any engine, especially the 19J. The other thing to consider is to lower the boost pressure a little. I have done this and also fitted the military 2.5NA cyclonic breather to my 19J to protect the air filter from getting clogged with oil. I think the breather system even on the later 19J engines still had scope for improvement to something more like on the Tdi engines.

[SanDiego110]

I've scrutinized the crack-prone areas... no cracks are visible with my eye. Should I use a dye penetrant? Maybe there are cracks I can't see. You guys have convinced me that a 19J free of cracked pistons/combustion chambers is somewhat of a unicorn. 

[monkie]

On 08/01/2018 at 3:29 AM, SanDiego110 said:

If and when you fix your write up, let me know, it would be very helpful.

Here you go, ignore the first post directing you to the LRO forum (now dead).

 

[Snagger]

15 hours ago, Landrovernuts said:

It would be interesting to know how well the 19J would last if it was fitted with a charge air cooler - not for extra go, but to drop the temperatures. May be piston life would be extended and cracking may well be reduced. 

I remember many moons ago someone fitting a 200tdi rad and intercooler set up to a 90 with a 19J and it fitted really easy with little modification work. I recall hearing good reports but nothing on if it made it last any longer. 

Toby

A mechanic friend suggested that to me a long while back.  My gut feeling is that it won't help, and could make things worse - the intercooler would reduce induction temperature but increase density.  The compression stroke would then have increased adiabatic temperature rise, and the combustion stroke would burn more of the injected fuel.  Which of those effects would be dominant would dictate whether the the intercooler affects longevity, but you'd need to try it on several engines of identical condition to get any useful data.

[monkie]

^^^ My feeling exactly. I have looked through engineering literature and can find no tried and tested evidence for intercoolers reducing thermal stress on piston crowns.

I followed your suggestion following my rebuild of turning the charge pressure down just a couple of PSI. Made no noticable difference to performance. Also I mentioned above, regular servicing, set of recon injectors, improved breather sytem and above all sympathetic driving. about 20k miles done so far since rebuild with no issue yet (slight oil leak to sort out at the front when the weather is warmer)....

[toenden]

I once had a 19j which I ran for numerous years with no problems. The engine had a rebuilt early in its life at 100k km when it broke the bottom of a piston and tried to out the piston out the side of the block. It did get home on its own although running a bit harsh... my parents got the engine rebuilt and drove on for another 80k km pulling the family caravan and so on. At this age it was replaced with a 300tdi for the extra power and I "got rid" of the engine for them by putting it in my 90" along with an radiator/intercooler from an 300tdi (your are right, easy swop) and a boost upped to 0.9 bar for some unknown reason... here it lived for another 100k km with 1 change of the headgasket because it develloped a waterleak to the outside! It was used to pull horsetrailers normal community as well as rather heavy offroad. It got changed with a 300 to get some more power but was reused in yet another car where I lost track of it. It ran realy nice, had ok power and was reliable! (I know this isn't the normal opinion but I realy liked it)I remember thinking that the intercooler gave a feeling of some more lowdown power. 

There wasn't any obvious signs of cracked pistons when we opened it to do the headgasket but I didn't remove any pistons to check thoroughly. It didn't breathe and didn't use oil or water. The breather was removed from the airfilter and put into a bottle, but I can't remember ever emptying the bottle... 😀

All i all a nice engine but a bit vintage and fragile.

 

/mads

[Snagger]

They do run so much more quietly and smoothly than Tdis.  Their reliability is a pity, as they'd otherwise be ideal for Series retrofits.

[SanDiego110]

I looked over everything and this is the only crack I could find... not even sure if it is a crack. This engine is in great shape for a 1989.

[Snagger]

I'm pretty sure that is a crack, and is where you'd expect to find them on these engines.  The problem with it is that if it spreads, it could allow the valve seats to drop, preventing the valves from fully closing and causing piston contact.  I don't know how viable it is to have it welded and the head recut to take new valve seats.

[SanDiego110]

Where is a good place to find a new or used head if it comes to that?

[Snagger]

Rovers Down South and East Coast Rovers are two US names I've heard of.  If you want a perfect job and don't mind the shipping costs, Turner Engineering are the best, literally better than new.

[monkie]

Have you taken it to a local engineering shop have it inspected and have a professional opinion on what can be done with it in terms of welding?

[SanDiego110]

Thanks, I'll make a note of those shops. I put the engine back together despite the crack between valve seats. It started right up and no more smoke (whoo hoo!!!). Still tinkering with a leaking steering box and a tiny oil leak. I'm prepared for some degree of disaster in the future given the unrepaired head crack, at least I know where to go now for a replacement. No monkie I didn't take it to a professional. Should have done that, but I doubt shops around here have that kind of experience.

[monkie]

Just keep a look out for a spare head. I have no idea how much it would cost to send one to the USA from the UK. I bought a couple of heads off eBay with no cracks in to keep as spares. I would be willing to sell you one of them if you like? Send me a pm if interested.