CNG Accent, Done 35k - Does it need an overhaul?

Atlblkz06 · 23rd March 2009, 20:12

Are the cylinder walls scored? Either you're getting blow-by - or the pieces may have affected your valves while your ran the engine. After a compression test, a visual inspection should give you the solution. If the cylinder walls are scored your best bet is to sleeve it or to re-bore it and get new pistons. Hell throw some forged components in there and add in a turbo since you're going that far anyway haha.

saintsinner · 30th March 2009, 03:50

thanks all, i have a hi scan and a compression test scheduled for this thursday at nimbus hyundai. hi scan will not be charged as i know them very well (official complaint 2 yrs back) and the compression test will cost 350 bucks.

saintsinner · 3rd April 2009, 07:36

ok, so here are the compression test results -

Dry
1. 14.5 Kgcm
2. 13.5 Kgcm
3. 13.0 Kgcm
4. 13.5 Kgcm

Wet -
1. 17.5 Kgcm
2. 17.0 Kgcm
3. 16.0 Kgcm
4. 17.5 Kgcm

quite obviously, it needs an overhaul. service center gave me an estimate of 45K and they said they will change almost every component. they will put a sleeve and use the same piston size.

I then paid a visit to Mr. Kapoor at Performance.
He said the expense he is looking at it one size oversize piston, piston rings, main bearing, gaskets and seals. he is yet to provide me an estimate. i have my reasons for not going in for a sleeve and Mr. Kapoor agreed on my views. the material of the block & sleeve is not same, their properties are different. when they heat up they respond differently. and then a size bigger will show some performance gain.

let me know what you guys think about this.

silver_shadow · 3rd April 2009, 17:15

what are the normal values for compression BTW? one more thing - does it need piston change or will rings do it?

saintsinner · 4th April 2009, 04:20

^ the service center says around 15 - 15.5 for this aged accent.

saintsinner · 5th April 2010, 03:37

posting after an year on this thread. The accent performs beautifully. it has done around 10K kms after the overhaul and gives me a mileage of 12-13 kmpl with AC. Hits top speeds of 180-185 kmph. the CNG kit was taken off and the car has been running on petrol ever since!

akshay4587 · 5th April 2010, 09:37

Quote:

Originally Posted by saintsinner

posting after an year on this thread. The accent performs beautifully. it has done around 10K kms after the overhaul and gives me a mileage of 12-13 kmpl with AC. Hits top speeds of 180-185 kmph. the CNG kit was taken off and the car has been running on petrol ever since!

How does it feel at those speeds

i never dared to push her beyond 160-165,though i have done 175 once

jigbarai · 5th April 2010, 10:03

Where did you get the overhaul done, what all was done and the cost factor ?

Most importantly : Was CNG kit to blame here ? Ppl put these gas kits to save money on fuel, but if that money is going down this overhaul drain its not good.

It has been what 2-3 yrs now since the CNG scene has really picked up. If thats the case, expect more of such issues to start cropping up now.

Abeer · 5th April 2010, 12:36

did you find out the reason behind the overheating?

saintsinner · 5th April 2010, 14:10

akshay - she feels great. mad acceleration!

jigbarai & Abeer - The CNG was partially to blame here. The new Accent has the beta engine and i have heard it doesn't handle CNG too well. the accent before 2005 had a alpha engine (i suppose) which gave trouble free operation.

I also have a CNG indica with a sequential kit, here is what i have learnt -

1. A car always heats up more on CNG. keep an eye on the temp needle specially in the summers with AC
2. CNG makes the valves run dry and some cars need a head job soon! Do run your car on petrol at times.
3. It is always better to go in for a sequential kit than the normal kit. It is worth the extra cost.

ask77 · 1st May 2010, 21:17

Quote:

Originally Posted by saintsinner

akshay - she feels great. mad acceleration!

jigbarai & Abeer - The CNG was partially to blame here. The new Accent has the beta engine and i have heard it doesn't handle CNG too well. the accent before 2005 had a alpha engine (i suppose) which gave trouble free operation.

I also have a CNG indica with a sequential kit, here is what i have learnt -

1. A car always heats up more on CNG. keep an eye on the temp needle specially in the summers with AC
2. CNG makes the valves run dry and some cars need a head job soon! Do run your car on petrol at times.
3. It is always better to go in for a sequential kit than the normal kit. It is worth the extra cost.

Can you give the cost of a new sequential CNG kit ?

23rd March 2009, 20:12	#16
Atlblkz06 BHPian Join Date: Jan 2009 Location: Atlanta Posts: 164 Thanked: 20 Times	Are the cylinder walls scored? Either you're getting blow-by - or the pieces may have affected your valves while your ran the engine. After a compression test, a visual inspection should give you the solution. If the cylinder walls are scored your best bet is to sleeve it or to re-bore it and get new pistons. Hell throw some forged components in there and add in a turbo since you're going that far anyway haha.
	() Thanks

30th March 2009, 03:50	#17
saintsinner BANNED Join Date: Jun 2007 Location: Noida Posts: 612 Thanked: 11 Times	thanks all, i have a hi scan and a compression test scheduled for this thursday at nimbus hyundai. hi scan will not be charged as i know them very well (official complaint 2 yrs back) and the compression test will cost 350 bucks.
	() Thanks

3rd April 2009, 07:36	#18
saintsinner BANNED Join Date: Jun 2007 Location: Noida Posts: 612 Thanked: 11 Times	ok, so here are the compression test results - Dry 1. 14.5 Kgcm 2. 13.5 Kgcm 3. 13.0 Kgcm 4. 13.5 Kgcm Wet - 1. 17.5 Kgcm 2. 17.0 Kgcm 3. 16.0 Kgcm 4. 17.5 Kgcm quite obviously, it needs an overhaul. service center gave me an estimate of 45K and they said they will change almost every component. they will put a sleeve and use the same piston size. I then paid a visit to Mr. Kapoor at Performance. He said the expense he is looking at it one size oversize piston, piston rings, main bearing, gaskets and seals. he is yet to provide me an estimate. i have my reasons for not going in for a sleeve and Mr. Kapoor agreed on my views. the material of the block & sleeve is not same, their properties are different. when they heat up they respond differently. and then a size bigger will show some performance gain. let me know what you guys think about this.
	() Thanks

3rd April 2009, 17:15	#19
silver_shadow BHPian Join Date: Apr 2008 Location: Bangalore Posts: 366 Thanked: 3 Times	what are the normal values for compression BTW? one more thing - does it need piston change or will rings do it?
	() Thanks

4th April 2009, 04:20	#20
saintsinner BANNED Join Date: Jun 2007 Location: Noida Posts: 612 Thanked: 11 Times	^ the service center says around 15 - 15.5 for this aged accent.
	() Thanks

5th April 2010, 03:37	#21
saintsinner BANNED Join Date: Jun 2007 Location: Noida Posts: 612 Thanked: 11 Times	posting after an year on this thread. The accent performs beautifully. it has done around 10K kms after the overhaul and gives me a mileage of 12-13 kmpl with AC. Hits top speeds of 180-185 kmph. the CNG kit was taken off and the car has been running on petrol ever since!
	() Thanks

5th April 2010, 10:03	#23
jigbarai BHPian Join Date: Sep 2009 Location: Mumbai Posts: 554 Thanked: 29 Times	Where did you get the overhaul done, what all was done and the cost factor ? Most importantly : Was CNG kit to blame here ? Ppl put these gas kits to save money on fuel, but if that money is going down this overhaul drain its not good. It has been what 2-3 yrs now since the CNG scene has really picked up. If thats the case, expect more of such issues to start cropping up now.
	() Thanks

5th April 2010, 12:36	#24
Abeer BHPian Join Date: Nov 2009 Location: UP-16 Posts: 222 Thanked: 18 Times	did you find out the reason behind the overheating?
	() Thanks

5th April 2010, 14:10	#25
saintsinner BANNED Join Date: Jun 2007 Location: Noida Posts: 612 Thanked: 11 Times	akshay - she feels great. mad acceleration! jigbarai & Abeer - The CNG was partially to blame here. The new Accent has the beta engine and i have heard it doesn't handle CNG too well. the accent before 2005 had a alpha engine (i suppose) which gave trouble free operation. I also have a CNG indica with a sequential kit, here is what i have learnt - 1. A car always heats up more on CNG. keep an eye on the temp needle specially in the summers with AC 2. CNG makes the valves run dry and some cars need a head job soon! Do run your car on petrol at times. 3. It is always better to go in for a sequential kit than the normal kit. It is worth the extra cost.
	() Thanks