[anujmishra]

My suggestions Samurai. Don't take is otherwise or non ethical

Pack this head, crank engine and find new customer. Look for other jeep. This would relieve most of the worries form you.

In this way, I think you can come out with little less expenses as changing head would cost you 40 grand.

[Samurai]

Since I am getting all kind of advices, I can't follow all of them. Therefore I have decided to follow Mr.Dhabhar's advice since he knows CJ/CL340 Jeeps extremely well.

His suggestion is as follows:

1) Weld the crack in the aluminium head.
2) Drain water from the cylinder block.
3) Put the valve back into cylinder head after lapping it properly. Use Mahindra recommended head gasket.
4) Remove the air cleaner and drain the pan and clean it completely.
5) Dry the air cleaner and put it back.
6) Check the rubber hose between air cleaner and intake manifold (replace hose if dirty, don't clean)
7) Remove fuel filter and replace it with Mahindra recommended mico fuel filter.
8) All fuel lines should be tightened properly.
9) Replace oil filter - same as Scorpio (purolator oil filter)
10) Check whether connecting rods are bent due to hydrolocking. See whether the piston levels with the crown of the DPC (??)
11) Fuel Injection timing (FIP) should be set according to manual.
12) Measure LxBxH of the radiator core, count number of rows of pipes, measure vertical fin density (fins/inch). [This is for information purpose]
13) Replace water pump.

Hope I captured his instructions on phone correctly. Once he confirms this list, I will hand the list to the service advisor.

[Mohnish]

Originally Posted by headers

Sir, we seem to have similar thoughts. Thanks for sharing your views!

Yep, I too was relieved reading your like minded opinion, but then deleted the post on account that Samurai wrote that the head was cracked. From the pics put up, there does seem to be a crack in the head.

I guess we have to back track our opinions for now !!! Was trying to avoid a major job if none was needed, but Samurai now is left with no choice.

[DHABHAR.BEHRAM]

Dear Samurai - I have edited the process as required, my additions are in BOLD.

Aim - to restore your car's engine parameters in the shortest possible time with least cost and highest value for money route. Therefore, it is a concious decision not to replace the cylinder head at this time. Following actions must be carried out to ensure above results. Any deviation will lead to incorrect results.

0) REPLACE ALL CYLINDER HEAD MOUNTING BOLTS WHICH ARE NOT TO OE SPECIFICATIONS. THIS MUST BE DONE WITHOUT FAIL. It is necessary to clean all the internal threads in the cylinder block. For this purpose, assemble the bolts into the cylinder block holes without the head in place and rotate them with a speed spanner until the thread interference cleans the thread and tightening operation is smooth.

1) Weld the crack in the aluminium head - first check the depth of the crack, confirm its location in the engine and its effects on engine operation. Weld the crack and hand file it to match the cylinder head face. This operation is very delicate and must only be carried out by a person having requisite skill. Failure to perform this operation properly will render the cylinder head not useable. Red flag item.

2) Drain water from the cylinder block - although the cylinder head is opened so the water has drained off, some residual water remains in the passages inside the cylinder block. This needs to be drained off. There is a drain plug in the side of the cylinder block.

3) Put the valves back into cylinder head after cleaning and lapping them properly. Use Mahindra OEM head gasket only - check for valve seat integrity by testing the same with a leak tester. Avoid replacing valves as it leads to further complications in the reconditioning process at this stage.

4) Remove the air cleaner completely out of the car and drain the pan and clean it completely - pressure wash the air cleaner with water and dry it. If the wire mesh is found damaged, replace the air cleaner assembly complete. Use M&M OEM part only.

5) Dry the air cleaner and put it back - fill with new recommended grade of oil to correct level.

6) Check the rubber hose between air cleaner and intake manifold (replace hose if dirty, don't clean) - this is known as the "clean air" hose. It is necessary to ensure absolute cleanliness of the ID of this hose. Use M&M OEM hose only if required.

7) Remove fuel filter cartridges and replace them with Mahindra OEM cartridges only, irrespective of whether they were replaced recently or not.

8) All fuel lines should be tightened properly - use new sealing washers as per M&M part catalogue at all ends. Check for joint integrity. Check for any kinks in fuel lines. Non confirming lines must be replaced.

9) Replace egine oil irrespective of whether it was replaced recently or not - use Mahindra Maximile supreme oil only. Also replace engine oil filter - use M&M OEM XDP4.90 engine recommended filter of purolator make as per part number.

10) Check whether connecting rods are bent due to hydrostatic lock. See whether the piston levels with the crown of the cylinder block. - this is a very rough check. As the cylinder block is not being opened at this stage, no further inspection is possible. The combustion chambers in the pistons appear to be OK.

11) Fuel Injection timing (FIP) should be set according to manual - your comments on smoke colour etc seem to indicate that the FIP timing of your car is advanced as compared to XDP4.90 specifications. However, this operation must be carried out AFTER starting the engine and observing its behaviour for power delivery, NVH and smoke colour. DO NOT RESET FIP TIMING NOW.

12) Measure LxBxH of the radiator core, count number of rows of pipes, measure vertical fin density (fins/inch). [This is for information purpose] - I await this information. Also check the number of tubes in each row from one side to the other. Remove the radiator from the car, temporarily block the hose apertures and fill it to capacity with soft water. Measure the capacity in cc and inform me.

13) MOST IMPORTANT - Replace the water pump assembly. Use M&M OEM part only. DO NOT - REPEAT - DO NOT USE THERMOSTAT IN THIS CAR AT THIS STAGE. After all trials are completed, we will fit a brand new thermostat.

14) IMPORTANT - clean water pump mounting threads in the cylinder head before assembling the new water pump. Ensure smooth operation of all fasteners.

15) Torque the cylinder head as per M&M procedure before assembling the rocker arm and confirm torque with a crow-foot spanner after assembling the rocker arm.

16) Fit a brand new fan belt. This engine dress level seems to be of single belt type. Check for dress level and use OEM part only.

PLEASE GO AHEAD AND BEST OF LUCK.

Hope I captured his instructions on phone correctly. Once he confirms this list, I will hand the list to the service advisor.

Best regards,

Behram Dhabhar

[mjothi]

This thread become like a encylopedia on CJs. Good inputs. Thanks Samurai for starting this thread.

[Samurai]

Thanks for the very detailed correction Mr.Dhabhar, I will send this list to the service advisor.

Originally Posted by sudev

@Samurai: Pardon my ignorance. The crack is between water body and head bolts. How is that effecting the engine?

This is not the reason for leak, look at second photo at the red circle.

[Mohnish]

Originally Posted by sudev

@Samurai: Pardon my ignorance. The crack is between water body and head bolts. How is that effecting the engine? Coolant will drip away but engine power/compression should remain intact...

In pic 1 there is shown a blown gasket, that would allow hot combustion gasses to enter the cooling system = overheating.

Originally Posted by anujmishra

My suggestions Samurai. Don't take is otherwise or non ethical

Pack this head, crank engine and find new customer. Look for other jeep. This would relieve most of the worries form you.

In this way, I think you can come out with little less expenses as changing head would cost you 40 grand.

IMHO & With all respect Anuj, I disagree with you. Totally not done to dump it onto some unsuspecting/trusting buyer.

Originally Posted by DHABHAR.BEHRAM

Dear Samurai - I have edited the process as required, my additions are in BOLD...

Aim - to restore your car's engine parameters in the shortest possible time with least cost and highest value for money route. Therefore, it is a concious decision not to replace the cylinder head at this time. Following actions must be carried out to ensure above results. Any deviation will lead to incorrect results....

Absolutely amazing, excellent instrctions. I certainly hope that DHABHAR.BEHRAM is here to help me out if, God forbid, I am in this kind of trouble.

[BaCkSeAtDrIVeR]

This engine dress level seems to be of single belt type. Check for dress leve

@Dhabharji, what is "Dress level"??

Re the odd size studs - I have seen studs replaced (bolts with threads at both ends - one end goes into the block and the other end fastens something on to the block - like a fuel pump, head, water pump, etc) using a nut) with an oversize thread on the head side.

Doing this is required when the engine is overhauled for 3rd or 4th time. So, how many overhauls has this engine seen?

For such "oversize" studs, except for threads going into the engine block, everything is normal size. Only way to take back the studs to normal size is to weld the hole shut and re-bore that. Obviously, not recommended.

About the head - just in case you do not want to weld the head, consider searching around for a second hand head in your local chor bazar. The mechanics would know where it is.

[sudev]

@Samurai : Thanks for the patient explanation. Watching this restoration carefully. One suggestion - for head welding find a good workshop even if you have to send the head to Banglore/Mumbai.

[DKG]

Behram you are a gem

[dinar]

Nice info on the jeep engine engine Behram, but the welding the head part is little scary though.
But really good to know someone who can help this way on M&M engines. Now I can think of buying another Jeep..
So samurai whens the work on the engine starting?Hope you get good person to do the welding, if not there are a couple of workshops in belagum [the place is know for this kind of work on any engine].

[RedMM340]

Samurai,

I would not recommend that you weld the cylinder head. The head would just be unreliable, and spring a leak when you least expect it. If the head or block is cracked, it is as good as scrap metal in my opinion.

You asked about what type of nit-wits would drill wider than standard holes? Well these are the same type that would also weld a cylinder head. This is all under the category of desi-jugaad.

Get a new cylinder head and do the repair right.

I spent about 70K doing the overhaul for my motor using all genuine M&M parts. Cylinder head, pistons, rods, valves are new.

[nitrous]

Samurai, Send that jeep and 30k instead to Chennai. We'll send it back with a 2.5 XD3 bolero engine. What say?

[nitrous]

Originally Posted by anujmishra

My suggestions Samurai. Don't take is otherwise or non ethical

Pack this head, crank engine and find new customer. Look for other jeep. This would relieve most of the worries form you.

In this way, I think you can come out with little less expenses as changing head would cost you 40 grand.

Don't take offense,anuj.
But, there is a LOT more to jeeps than you know.

[DHABHAR.BEHRAM]

Dear Samurai - ref your PM, looking at the pictures you have posted, I feel that the crack is superficial and need not be welded because welding carries its own complications. However, please perform following operation in order to generate more confidence in our assumption, based on which we take a call. Place the head on a bench, take a broken hacksaw blade and grind it to a sharp point. Then try and insert it in the crack from all locations, including its propagation in the water jackets. Make out a physical list of the depth of the crack at various locations and for each of these locations, write down what worst case scenario it will present to you. This is a sort of risk assessment sheet which will finally reveal the degree of seriousness that this crack presents to the wellbeing of the engine. I understand that this requires good analytical capability but that's the best I can offer you sitting 1800 kms away. Try it out, it will tell you what you are up against. In any case, in the worst case scenario, you will have to put a new head, no harm in trying. I await radiator dimensions also.

Dear backstreetdriver - "dress level" essentially means that for different applications of a base aggregate (like an engine or a transmission), the build level changes as the build progresses. A base XDP4.90 engine can be dressed (adapted) for AC / non-AC / Armada / Bolero / MM540 / BS1 / BS2 / BS3 / with oil cooler / without oil cooler / peaking @ 4000 rpm / peaking @ 4500 rpm / non-automotive applications etc. There is no end to it. Essentially different accessories are fitted for different applications. e.g. for Bolero, the water pump is different with a degassing tank or without a degassing tank. In case of Samurai's CL340, there is only one accessory driving belt, previously there used to be two. The engine is built to pre-BS1 non-AC dress level. It is necessary to confirm the exact dress level and order parts as per the relevant part numbers. I hope I have clarified.

Dear DKG - thanks for your comments. I know.

Best regards,

Behram Dhabhar