Compression Test/ Leak Down Test Info Req,

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rustam54 (rustam) 2011-09-14 04:17:59 +0500 #1

Dear All,
Well i am having a problem lately that my car (Cultus 06 Carby) is starting to lose power in the top gear around 100 km/h esp when AC turned on. It gradually comes down to 80 and starts missing. I dont know whats the reason. Also i am not able to get it to 120 that easy now. Have to rev up a bit more in lower gears to get there. But there wasn't a problem long ago. Happens on both petrol and CNG. Though less prominent on petrol.

I have been told that it can be an exhaust valve issue. The insufficient compression becomes prominent at high engine load. For that I have been searching around ways to identify such cause and as the title says, compression and leak down tests seem to be the only way without head opening to pin point the cause.

Can anybody tell me where in Lahore can i find a compression gauge or workshop/mechanic that does this test. A wild guess would be suzuki dealerships but not sure. Also does anybody have an experience to make a custom leak down test hose??? I believe for that one doesn't necessarily require a gauge. just a 5-10 bar from regular air compressor at TDC would highlight the leaks, wouldn't it??

P.S. It doesnt consume Oil/coolant/blow bubbles in radiator/blows smoke in cam chamber etc. None of it.

Inputs/ suggestions/ comments/ welcomed.

Regards,

Nauman

EDIT1 : The actual query/ concern of the availability of the tester has been resolved. The thread is now intended to move towards resolution of the issue.

EDIT2: The issue has been resolved. Compression gauge helped to save the head and valve work. The culprit was "Retarded Ignition Timing"

Skill (Skill) 2011-09-14 10:09:10 +0500 #2

there is no compression tester locally in lahore or even in islamabad,even 95 out of 100 mechanics are not even familiar with compression tester here,they just do work with "teer tuka",they will pull and push back the cords of plugs and make you fool,thats it.
Yes i believe enercon guys have a little sense.

rustam54 (rustam) 2011-09-14 11:55:01 +0500 #3

^Thank you for your inputs. Thats exactly my point sir. A mechanic would tell me to get a engine head and valve job without even identifying the faulty cylinder.

So i wanted to do a DIY and first hand analysis.

Xulfiqar (Xulfiqar) 2011-09-14 12:16:20 +0500 #4

what engine oil are you running? this problem occurs in most hydraulic tappet engines when the oil used is too thick and the lifters and oiling galleries are full of sludge.

rustam54 (rustam) 2011-09-14 14:03:16 +0500 #5

Sir i am using Shell HX7 10W-40 since the beginning.
Shell Helix HX7 - Products & Services

As far as i can tell, there is no sludge right now. Let me post a couple of snaps for reference. Maybe you can tell better by the looks of it.

Xulfiqar (Xulfiqar) 2011-09-14 14:06:37 +0500 #6

that does look clean - do a compression test on a hot engine. and check all breather hoses/pipes too.

rustam54 (rustam) 2011-09-14 14:12:10 +0500 #7

but where to get the gauge??? Is there any way to make one. I can ask the khuradia to make something for me given an off the shelf prssure guage. But that would take like ages to tell him what to make.

rustam54 (rustam) 2011-09-16 07:33:19 +0500 #8

Bump!!

Any other inputs from fellow members???

margallar (margallar) 2011-09-16 07:39:10 +0500 #9

i dunno the place where to get it done. but this will give you an idea how to do it

//youtu.be/http://www.youtube.com/watch?v=ovvXnd7AhiU

isi0000 (isi0000) 2011-09-16 07:39:34 +0500 #10

once i asked rozz bhi about this and he told me to check at maxtorque 1-10 ibd.......
adeel bhi at shop replied that it can be done just pay a visit......but i couldnt get there just because of laziness......contact rozz bhi he may help u....

margallar (margallar) 2011-09-16 07:50:12 +0500 #11

^does maxtorque have a branch in lahore?

razapower (razapower) 2011-09-16 08:35:37 +0500 #12

compression test is not a big deal guys .
Buy the gauge yourself or get it done from Nazir G-8, or honda or toyota authorized dealers.

margallar (margallar) 2011-09-16 08:51:02 +0500 #13

wesay how much does it cost?

Proverbial_Slang (Proverbial_Slang) 2011-09-16 08:53:07 +0500 #14

@OP, try Montgomery road or Brandreth road. Also check with Suzuki dealers for compression testing.

Cultus does not have hydraulic lifters.

rustam54 (rustam) 2011-09-16 14:05:35 +0500 #15

Thanku sir. I'll try brandreth road. I dont think montgomery guys would have it.

Correction. 06 Carby Cultus does have hydraulic lifters. Right beneath the cam lobes. Otherwise you would have seen mechanical lifter arms parallel to the cam in the above pics.

Xulfiqar (Xulfiqar) 2011-09-16 14:17:51 +0500 #16

yes it does, thats why those lifters do not have any adjustment shims on them and have a little piston inside them that take up play (clearance) Go to a mechanic who is repairing a cultus 3 cyl head and ask him that you want to see if the lifters (dubboo) are hydraulic (automatic in their language)

Xulfiqar (Xulfiqar) 2011-09-16 14:19:45 +0500 #17

the tester is cheap, mine cost Rs 1000/- in 2002 and is still good for work. Dont know about now, I would say double that. Its a good tool to have. I also have ones I bought earlier (mid 90s) and they were borrowed and forgotten by former freinds.

levin (levin) 2011-09-16 14:27:30 +0500 #18

buy yr own guage. read the manual and do it yrself
or take to any mechanic, he will open plugs so you can fit guage in.

its not hard

Sharo53 (Sharo53) 2011-09-20 14:54:11 +0500 #19

if the mentgomery road is not much far from your place then go to chevrolet dealership near mentgomery road i saw a compression tester there some time back

rustam54 (rustam) 2011-09-21 14:53:51 +0500 #20

Well fellows, i was able to get the gauge and perform the compression test.

The engine was first heated up to normal operating temperature. Then dry and wet tests were performed. Following are the results i would like to share.

Cylinder 1 : Dry-171 psi , Wet - 200 psi
Cylinder 2 : Dry-179 psi , Wet - 205 psi
Cylinder 3 : Dry-178 psi , Wet - 198 psi

As far as i can tell, the variation between the cylinders is within limits. However i have some concerns regarding dry and wet differences

I couldnt find the maintenence manual of G10. However on some forums of Geo Metro (having a G10 as well) they say it should be with-in 180 to 190 psi for dry and somewhere around 200+ for wet cylinder compression.

I would like to request the experts to share their views.