[Jeroen]

Originally Posted by Leoshashi

Why not go the half engine way?? IIRC it's price was around 32k for the Zen and even though it will be more expensive than overhauling the conventional way, I believe it will be worth it as half engines are assembled as per factory specs.

What does this really mean go the half engine way? What is being overhauled and what not.
Thsnks
Jeroen

[Leoshashi]

Originally Posted by Jeroen

What does this really mean go the half engine way? What is being overhauled and what not.
Thsnks
Jeroen

In the conventional way, the engine is taken apart, every single component is inspected for tolerances, sent to lathe if necessary, and then assembled back. Since it involves lot of manual labour, its both time consuming, and the quality of overhaul is inconsistent. There are some mechanics who are able to get excellent results, whereas in some cases, the engine becomes a money pit.

I am not too sure about other manufactueres, but Maruti has option of half engine replacement for all its cars. Half engine is basically block+piston+con rod+crankshaft and other smaller bits pre assembled from factory. I personally prefer half engines over conventional overhauls as it's both quicker(takes a day for installation) and since it's assembled on the same lines where a brand new engine is assembled, its safe to assume that quality will be consistent and better.

Cost is approximately 20% higher than conventional overhauls. For example my friend recently went for half engine replacement, and the local FNG gave him an estimate of 20k for conventional overhaul. At MASS it was around 23k with half engine replacement.

This is how a half engine looks:







Regards
Shashi

[Sutripta]

Originally Posted by Jeroen

What does this really mean go the half engine way?

Better known as short block.

Also used to be commonly available for the 1100/ Padmini.

@ Sashi - What is the exact description in the parts catalogue.

Regards
Sutripta

[Leoshashi]

Originally Posted by Sutripta

@ Sashi - What is the exact description in the parts catalogue.

Regards
Sutripta

Mostly Half Engine Assy and sometimes Short Engine Assy in Maruti terms.

Also, most of the parts catalogue, specially those of older models like M800 don't mention anything about the half engine. Newer ones like S Cross have a dedicated page at last mentioning part numbers of larger assemblies and body shells.



Regards,
Shashi

[Jeroen]

Interesting. What do you do with the cilinder Head, valves, Valve stems, seats and all the rocking gear?

[Leoshashi]

Originally Posted by Jeroen

Interesting. What do you do with the cilinder Head, valves, Valve stems, seats and all the rocking gear?

They are changed/serviced as per requirement.

Recently my friend had to change the half engine on his car, and his head and all associated parts were left untouched(except cleaning the head and re-seating the valves). However, they measured the tolerances of each old part before reusing them.

Regards,
Shashi

[Jeroen]

Originally Posted by Leoshashi

They are changed/serviced as per requirement.

Recently my friend had to change the half engine on his car, and his head and all associated parts were left untouched(except cleaning the head and re-seating the valves). However, they measured the tolerances of each old part before reusing them.
i

Thanks Shashi,

do you have some idea at what interval (i.e. mileage) these engines get the half treatment?

I must admit, I had never heard of this. These days it is very rare for the engines of modern cars for normal use to be completely overhauled.

Overhauling is mainly done in the classic car scene on very old engines with very high mileage, say well above 200-300K. Cilinderheads might be overhauled at lower intervals, depending on make/brand etc.

There are plenty of very capable, specialised workshops around. And quite a few of them will be able to do a full engine overhaul well within manufacturing specifications. As labour is very expensive in the west, engine overhauling is not something that happens very often, unless the car is special in some sense. (e.g. a classic car)

Jeroen

[chiranjitp]

Originally Posted by Jeroen

Interesting. What do you do with the cylinder Head, valves, Valve stems, seats and all the rocking gear?

In 2013 our 99 Omni had to go through an engine overhaul, it had done around 90k km. The engine was consuming oil at a high rate, there was white smoke from the exhaust & engine oil in spark plug (which resulted in misfiring). We also went the half engine way, the half engine for F8B engine costed us around 12k. After fitting the new block (half engine) we had to get the engine number updated in the registration certificate (the new block had its own unique engine number).

As for what was done with the head & its parts, I am not quite sure as to what was changed. But from the bill it seems that the parts were only cleaned & reassembled (like Leoshashi mentioned on his post). The total cost of the repair including brake overhauling & fluid change was 24k.

The main bill for the half engine. Notice the sticker at the top, this sticker had the engine number & other details of the new block.



One more bill from MGP store



The final bill from the FNG

[Leoshashi]

Originally Posted by Jeroen

Thanks Shashi,

do you have some idea at what interval (i.e. mileage) these engines get the half treatment?

That depends a lot on the way that engine has been maintained over the years, it's construction quality and other factors. I have seen some idiots needing half engine replacement in well under 50k kms, whereas some of the same engines have done more than 3 lac kms with ease. There is no hard and fast rule. Some engines are abuse friendly, some aren't.

There are plenty of very capable, specialised workshops around. And quite a few of them will be able to do a full engine overhaul well within manufacturing specifications. As labour is very expensive in the west, engine overhauling is not something that happens very often, unless the car is special in some sense. (e.g. a classic car)

Yes, labour in the West is expensive, but workmanship is also very good. I have seen some overhauling videos on YouTube, and the way it is done, I won't worry if half engine isn't available for my model.

[Jeroen]

Originally Posted by chiranjitp

In 2013 our 99 Omni had to go through an engine overhaul, it had done around 90k km. The engine was consuming oil at a high rate, there was white smoke from the exhaust & engine oil in spark plug (which resulted in misfiring). ]

Thanks for sharing, interesting. Of course, white smoke is typically not oil related.

Is this what you were sort of expecting in terms of mileage. An overhaul after 90k KM seems a bit early. I rarely buy my cars with less than 90K on them. Of course India is a harsh environment, but still.

Jeroen

[chiranjitp]

Originally Posted by Jeroen

Is this what you were sort of expecting in terms of mileage. An overhaul after 90k KM seems a bit early. I rarely buy my cars with less than 90K on them. Of course India is a harsh environment, but still.

I personally was expecting the engine to go past the 150k km mark, our relative's 97 M800 carb (same engine as our omni) did close to 200k km before requiring an overhaul. I think any engine should go past the 100k km even in a harsh environment like India if maintained properly. I was 5 years old when dad bought our Omni home (1999), so I am not quite sure if the oil changes were carried out at the specified intervals & my Dad is not exactly a petrol head. Anyways 90k km in 14 years means a average yearly running of around 6000 km, so I believe even if the yearly service was missed, our Omni didn't run more than 10000km without an oil change.

Till 2012, the Omni was running perfectly (zero breakdown). After the Punto came home in 2012, dad stopped driving her & we hired a driver for my Tuition duties. In early 2013, the fan belt snapped (Omni has a mechanical fan) & the driver drove around 40 km with an overheating engine . I was later told that the engine would die because of overheating & would not restart until the engine cooled down. After that incident the Omni became terribly unreliable (frequent breakdowns) & the problems were amplified by the incompetent mechanics. Finally in late 2013 it was decided that the engine needs to be overhauled. Even today I am not quite sure of the cause that made our Omni go through an engine overhaul at 90k km.

[jonesanto]

Like Shashi mentioned, engine life depends on how you maintained the vehicle. Cars operation consist of 100 things coming into play at the same time. Even if you overlooked some small things, in the long run it can effect the engine's life. I remember my friend was running with a leaking radiator, pipe had a minute leak, he used glue or something to stop the leakage and the leaking stopped, it went on fine for about 2 years or so, then one fine day, engine overheated and stopped. Ended up changing the entire radiator and luckily no damage was done to the engine, but definitely this would have effected that engine's life a bit for sure.

We can see countless Innova's cross 200K and running fine, I see a lot Lancers done close to 300K and still running. Some engines can take little abuse.

But in the end, it's all about how you maintained the vehicle from day one.

[im_srini]

Originally Posted by Jeroen

What does this really mean go the half engine way ?
What is being overhauled and what not.

Originally Posted by Leoshashi

In the conventional way, the engine is taken apart, every single component is inspected for tolerances, sent to lathe if necessary, and then assembled back.

Just to expand a bit on what Leoshashi has mentioned, at the "lathe" shop ( or turning-works ), if the wear is high enough, the cylinders are over-bored to accept oversize pistons ( Maruti sells oversize pistons in 2 sizes, the "1st oversize" is 10-thou & the "2nd oversize" is 20-thou ).

As you can imagine, this is whole "lathe" thing's usually a hit or miss affair depending largely on the competency of the lathe shop & the machinery / tools they use.
With the "half-engine" route, you get a fresh block with all the reciprocating & rotating bits assembled to spec

Originally Posted by Leoshashi

...
This is how a half engine looks:
...

This is an F10D half-engine, isn't it ?
Bought an F10D half-engine a couple of years ago myself




In general, the half-engine is used as is since it is assumed that it's kosher as it's directly from the factory - I would advise against this practice.
In my case, when I disassembled the half-engine, I found evidence of poor storage.
There was a neat divot of rust on one of the crank's main-bearing journals from water that had accumulated in the oil groove of the main-bearing !

[Jeroen]

Originally Posted by im_srini

Just to expand a bit on what Leoshashi has mentioned, at the "lathe" shop ( or turning-works ), if the wear is high enough, the cylinders are over-bored to accept oversize pistons ( Maruti sells oversize pistons in 2 sizes, the "1st oversize" is 10-thou & the "2nd oversize" is 20-thou ).

As you can imagine, this is whole "lathe" thing's usually a hit or miss affair depending largely on the competency of the lathe shop & the machinery / tools they use.
With the "half-engine" route, you get a fresh block with all the reciprocating & rotating bits assembled to spec

Thanks for the information. Interesting concept. As I said, I’m not familiar with any of the western manufacturers offering these “half-engine”. Engines typically get overhauled by specialised workshops and they tend to be very good at it.

And as I explained, usually on special/classic cars. Most classic car owners would probably prefer to keep the original engine during a restoration, rather then swap. Partly sentimental, but also financial reasons. The more original a car is the higher value it is likely to have.

The engine on my Alfa Spider was overhauled and new, slightly larger pistons were fitted. In my case, the Alfa Dealer I bought it from, did these engine overhaul as standard on all cars he restored. He brought some 12-16 Spiders across from the USA every year. On each car he would take the engine and gear box apart, check for wear and replace a few parts for wear and or some modifications. All cars were resprayed in the colour of your liking, re-assembled, new hood, new tires etc.

Typically these Spiders would all have at least 90-100K miles on the clock. And usually had been sitting idle for considerable time before they made it to my dealer friend.

Jeroen

[Leoshashi]

Originally Posted by im_srini

This is an F10D half-engine, isn't it ?
Bought an F10D half-engine a couple of years ago myself
[

I have used your pic only, Sir.

Originally Posted by im_srini

In my case, when I disassembled the half-engine, I found evidence of poor storage.
There was a neat divot of rust on one of the crank's main-bearing journals from water that had accumulated in the oil groove of the main-bearing !

How old was your engine?? When we bought a new half engine for my friend's car, I was aware of the issue which you faced(you had mentioned in another thread) and hence we went for the absolutely fresh piece. Rejected one or two month old ones. We changed it in Feb 2017 and the Packaging date and Manufacturing date was both Feb 2017. Since F8B half engine is so widely needed, I guess that helped our case as well.