[Spitfire]

@Sir: Oh didnt know about the coolant part. Now i understand the "wet" and "dry" liner part. Looked at both the engines(Bolero and Classic) and didnt make out. But when i had thought o rebuilding the engines i was told that in the Classic you will get the liner and piston. Useful info thanks a lot. Clears a lot of stuff for me.

Now to meditate..

[headers]

Originally Posted by DHABHAR.BEHRAM

Dear Dirty Dan - the answer to your second question first - in wet liner, the coolant touches the liner, in dry liner the coolant does not touch the liner. Therefore in the bare cylinder block of a wet liner engine, THERE IS NO BORE ALONG THE FULL LENGTH OF THE BLOCK. The cylinder block has a bored out ID at it's top and bottom ends and a liner is PRESSED in it. How do you prevent coolant from spilling over into the sump and other undesireable areas? Simple - you use O rings to seal the bores. Liner projection above the deck height of the cylinder block is a critical design parameter. In dry liner engine, the block has the primary bore or there may be a liner pressed in the bore on the block in which the piston moves. In any case, this liner does not come in direct contact with the coolant and is therefore called "dry". I hope everything is clear now. If you bugger up a wet liner engine, you can make it as good as new by replacing the "piston and liner" set available. As this is pre-machined, you are not left to the vagaries of an incompetent machine shop. Now to answer your second question - the MDI/TC is essentially a very robust and simple engine. Peak crankshaft speed is 3200 rpm. Torque @ low speeed is very good. Contrary to all expectations of power etc, the turbocharging is done to meet the ever increasing emission norms. There are 2 versions, the MDI/TC with gear driven csamshaft and the MDI/TC with chain driven camshaft. The former is used in utility vehicles. The latter is used in the Scorpio M2DI.

Best regards,

Behram Dhabhar

Sir, So if a wet liner engine looses compression - one does not rebore the entire block? Just change the liners and the pistion set with rings, right?

It makes matters simpler, i guess, whereas in the dry liner, one has to rebore the cylinder - Am i right?

[DHABHAR.BEHRAM]

Yes Headers, you are correct.

Further, remember, a rebored engine will perform depending on the bore integrity (meaning the honing pattern, it's surface finish etc). I do not wish to cast any doubts on anybody's capability, but more often than not, reconditioning workshops are small businesses who may not have the requisite facilities to recondition a bore to engineering specifications which are extremely tight today. Therefore, I tend to stay away from such activities. Please note that if you have a new diesel engine in your car, if you supply it with clean fuel, clean air, clean coolant and clean lubricant, there is no reason why the engine should not deliver expected life (incidentally expected life in customer usage terms is 3.5 lakh kms). Believe you me, more than 90% of engines come for reconditioning because the owner did not change the oil and air cleaner element at the correct time. I cannot understand this, people will try to save on oil and air cleaner element and then pay through their noses for an overhaul which may not work properly. I have cases of engines exceeding 3.5 lakh kms without an overhaul (believe me, I know). Think about it.

Best regards,

Behram Dhabhar



Best regards,

Behram Dhabhar

[vinod_nookala]

Originally Posted by DHABHAR.BEHRAM

Yes Headers, you are correct.

Further, remember, a rebored engine will perform depending on the bore integrity (meaning the honing pattern, it's surface finish etc). I do not wish to cast any doubts on anybody's capability, but more often than not, reconditioning workshops are small businesses who may not have the requisite facilities to recondition a bore to engineering specifications which are extremely tight today. Therefore, I tend to stay away from such activities. Please note that if you have a new diesel engine in your car, if you supply it with clean fuel, clean air, clean coolant and clean lubricant, there is no reason why the engine should not deliver expected life (incidentally expected life in customer usage terms is 3.5 lakh kms). Believe you me, more than 90% of engines come for reconditioning because the owner did not change the oil and air cleaner element at the correct time. I cannot understand this, people will try to save on oil and air cleaner element and then pay through their noses for an overhaul which may not work properly. I have cases of engines exceeding 3.5 lakh kms without an overhaul (believe me, I know). Think about it.

Best regards,

Behram Dhabhar



Best regards,

Behram Dhabhar

Dhabhar ji,

3.5 lakh kms for a 2.1 XDp engine with proper service record? Are you sure ? I gues GTo maintained his engine pretty well, always going to authorised service outlet and his jeep has been owned single handed. The why did his engine loose steam at about 1.6 lakhs?

I have seen well maintained boleros loosing steam at about 2 lakhs best. I agree about NEF delivering more than 3 lakhs. But an XDP engine 3 lakhs, never heard of it!!!

[headers]

Originally Posted by DHABHAR.BEHRAM

Yes Headers, you are correct.

Please note that if you have a new diesel engine in your car, if you supply it with clean fuel, clean air, clean coolant and clean lubricant, there is no reason why the engine should not deliver expected life (incidentally expected life in customer usage terms is 3.5 lakh kms). Believe you me, more than 90% of engines come for reconditioning because the owner did not change the oil and air cleaner element at the correct time. I cannot understand this, people will try to save on oil and air cleaner element and then pay through their noses for an overhaul which may not work properly. I have cases of engines exceeding 3.5 lakh kms without an overhaul (believe me, I know). Think about it.

yES sIR, I agree 100%. A person known to me had a contessa classic which ran upto 3.5 lakh kms and kept running until he decided to sell it. I have seen his OMNI - Maruti also cross 1.5 lakh kms before a rebore.

Originally Posted by vinod_nookala

Dhabhar ji,

GTo maintained his engine pretty well, always going to authorised service outlet and his jeep has been owned single handed.

Ha Vinod, thats a big big question mark. Now lets not get into contraversies.

GTO must / should have maintained his jeep well. Maybe lady luck did not work for him.

[DirtyDan]

Good description, Behram, pretty easy to follow you on the wet/dry liner story. Sounds like height and o-rings are critical and finicky but once installed properly you have a new tight engine.

I enjoy your tech posts. Thanks.

[DHABHAR.BEHRAM]

Dear Vinod Nookala - a CL340 with XDP4.90 covered 27 great escapes. When it got sold, the engine was as good as new. No secret - only meticulous maintenance. Incidentally after 27 great escapes, there was not a single dent on any wheel rim also. IT CAN BE DONE.

Best regards,

Behram Dhabhar

[nitrous]

@DB: What engine oil did you use? Grade and standard?
Oil change interval?
Did you run the oil bath air filter or the paper element one?
How often did you dust the air filter?
Fuel filter change interval?

[GTO]

Come on, Mr. Dhabhar....3.5 lakhs on an XDP! Even the manager of Milestone got his CJ340's engine overhauled at a little over a lakh kms. Maybe there has been an engine or two that went over 2 lakh kms, but they'd be an exception rather than the rule?

[DHABHAR.BEHRAM]

Dear GTO - please mark my verbatim. I have nowhere named the engine which actually worked for 3.5 lakh kms. However, I am also clear that if a new properly running diesel engine is supplied with clean fuel, correct and clean lubricant, clean coolant and clean air, I do not see any reason why a diesel engine should not work for 3.5 lakh kms. Just for reference, an engine goes through at least 4 times severeity in a life test on an engine dynamometer as compared to what it does in a car. In a car, the loading cycle is very lenient, it is nowhere close to critical.

Dear Nitrous - oil change interval = 10000 kms / foam element filter cleaned every 5000 kms and replaced every 20000 kms / fuel filter elements replaced every 20000 kms / due care taken during diesel filling to prevent any unwanted particles entering the tank / tank lid closed properly everytime / water pump drive belt inspected every 5000 kms and replaced at 60000 kms / water pump replaced every 100000 kms / vehicle driven mostly on highways approaching its maximum speed. You will observe that the car comes in for work only at every 20000 kms and not before that time.

Just for everybody's academic interest - clutch has worked for 136000 kms and it was OK when removed for inspection.

Best regards,

Behram Dhabhar

[tsk1979]

I tend to agree with Behram. I take care about service and air filter element change. Along with that I change gear oil also every 20K kms.
Clutch lasted 104000kms with still some life left. If I had not done severe clutch burning on himachal trips it would have lasted 15K more.
Engine is free from vibrations and there is no power loss, nor there are tell tale signs of damage like blue smoke etc.,

I change engine oil every 5-6K kms and change diesel filters every 10K kms. Use API-CI4 Castrol GTX diesel, even though procuring it is some struggle!

[DHABHAR.BEHRAM]

Sorry sorry forgot to provide some information on oil grade - the grade for diesel engine should read like this - MIL-L-2104 and then an alphabet. MIL-B is banned in India, so you see many ads saying "exceeding MIL-B" specification. Sad but true in our great country. Minimum need is MIL-C. MIL-D and MIL-E are available. MIL-F was made available as Shell Rimula by Bharat Petroleum some years back but has since been discontinued.

Best regards,

Behram Dhabhar

[tsk1979]

Mr Dhabhar, most Castrol etc., packs carry API-CF4,API-CG, API-CH4, API-CI4 and so on, thats why I prefer API-CI4 as its the highest grade available in market today

[akshay4587]

My Bolero GLX with XD3P engine has done 1.55 lakh kms now without a rebuild,just did 125 on speedo today(Dont ask how many minutes it took to reach that speed),it has just gone through regular periodic services,and still going strong,so 2L engine life can be achieved easily

[GTO]

Originally Posted by DHABHAR.BEHRAM

Just for everybody's academic interest - clutch has worked for 136000 kms and it was OK when removed for inspection.

Best regards,

Behram Dhabhar

Can't argue with that! My Classic's clutch lasted longer than the engine. It was fully functional on the 14th of Feb, 2006 which is when my 2.1 XDP collapsed (after a Valentine celebration ). That's a seriously heavy duty clutch that you guys use. I guess, 4x4s need a rugged clutch.