Team-BHP > Technical Stuff


Reply
  Search this Thread
41,621 views
Old 12th October 2013, 20:56   #16
Senior - BHPian
 
1100D's Avatar
 
Join Date: Jun 2006
Location: Calcutta
Posts: 4,390
Thanked: 4,068 Times
re: Trouble with my Fiat Uno Petrol. EDIT : Now Resolved!

Quote:
Originally Posted by Samba View Post
Update- But its negative.

Today morning my mechanic came with a spare fuel Pump. He fitted the new pump but the result was all the same.

As others specified here did the following check ups too-
1) once again cleaned the carburetor , checked the intake manifolds, and cleaned the carburetor jet too.
2) Opened the fuel pipes from the fuel tank and clean them once again.
3) Asked my mechanic to check the vacuum advance and ignition timing too.



This is Durga Puja time in Kolkata, we have seen Durga Puja 13 times in this car and in the 14 year its severely ill. But still for the peace of mind i took it for a 18kms spin in this condition itself. The car did the run with heavy knocking and lack of top end.

Now am thinking can it be the engine compression failing from one of the cylinders? But still there is no white smoke or decrease in the engine oil level. Engine temperature is also fine.

So more suggestions are most welcome!
Where did he get the spare pump from? New Pump or an old one?
1100D is offline  
Old 13th October 2013, 00:11   #17
Distinguished - BHPian
 
Samba's Avatar
 
Join Date: Apr 2013
Location: Kolkata
Posts: 2,172
Thanked: 25,396 Times
re: Trouble with my Fiat Uno Petrol. EDIT : Now Resolved!

Quote:
Originally Posted by 1100D View Post
Where did he get the spare pump from? New Pump or an old one?
The guy works with UB motors who deal with Fiat cars. So from their garage just to test he brought the fuel Pump. Before bringing he tested it in another Uno petrol over there and it was working perfectly. I asked him to do the test with the bottle but we could not get such long pipe as here all shops were closed today. Still as i insisted him to do that test once more. Next day he will bring a long pipe with him.

Last edited by Samba : 13th October 2013 at 00:22.
Samba is offline  
Old 13th October 2013, 11:29   #18
Team-BHP Support
 
Jaggu's Avatar
 
Join Date: May 2004
Location: Bangalore
Posts: 20,207
Thanked: 15,848 Times

Just check the valve settings and springs also. Might be a long shot but worth it. Also hope you have cleared off the electricals feeding the ignition circuit for any issues.

Since it's engine knock I have a feeling it's got to do something with timing side rather than fueling.
Jaggu is offline   (1) Thanks
Old 13th October 2013, 12:36   #19
Senior - BHPian
 
1100D's Avatar
 
Join Date: Jun 2006
Location: Calcutta
Posts: 4,390
Thanked: 4,068 Times
re: Trouble with my Fiat Uno Petrol. EDIT : Now Resolved!

Quote:
Originally Posted by Samba View Post
The guy works with UB motors who deal with Fiat cars. So from their garage just to test he brought the fuel Pump. Before bringing he tested it in another Uno petrol over there and it was working perfectly. I asked him to do the test with the bottle but we could not get such long pipe as here all shops were closed today. Still as i insisted him to do that test once more. Next day he will bring a long pipe with him.
Then Ignition and Fueling taken care of, if the problem is still there, I guess, its time for bad news. But before proceeding further, is there a way, this mechie can get you a compression test done? I for one, would only advocate for getting the head off, only if I am totally convinced that there is a problem inside.

No smoke, no contamination, is definitely indicating that your Oil and coolant circuits inside the engine-head is okay. A possible area of loss of compression can be gump deposit on the valves, or probably they are not seating properly. All that can actually also be negated, if the engine still shows a healthy compression.

I had a issue with my Ikon a few months back (knocking/missing above 5000 rpm and above 150), we checked everything, the Ford mechanic was hell bent on opening the head, saying its gotten old, I was not convinced, got them to do a compression test. Test supported the fact that the compression was healthy. Got them to get me a second "new" Fuel Pump, and voila, it was keeping up with an accord last weekend on our t-bhp meet.
1100D is offline   (1) Thanks
Old 14th October 2013, 01:25   #20
Distinguished - BHPian
 
Samba's Avatar
 
Join Date: Apr 2013
Location: Kolkata
Posts: 2,172
Thanked: 25,396 Times
re: Trouble with my Fiat Uno Petrol. EDIT : Now Resolved!

Quote:
Originally Posted by Jaggu View Post
Just check the valve settings and springs also. Might be a long shot but worth it. Also hope you have cleared off the electricals feeding the ignition circuit for any issues.

Since it's engine knock I have a feeling it's got to do something with timing side rather than fueling.
Thanks for the suggestion will surely do that. I missed on this. Once done will update you.

Quote:
Originally Posted by 1100D View Post
Then Ignition and Fueling taken care of, if the problem is still there, I guess, its time for bad news. But before proceeding further, is there a way, this mechie can get you a compression test done? I for one, would only advocate for getting the head off, only if I am totally convinced that there is a problem inside.

No smoke, no contamination, is definitely indicating that your Oil and coolant circuits inside the engine-head is okay. A possible area of loss of compression can be gump deposit on the valves, or probably they are not seating properly. All that can actually also be negated, if the engine still shows a healthy compression.
No my mechanic do not know a place where the compression test can be done. If you can suggest a place in Kolkata i can get it done over there, but again taking the car till there will be a huge task for me in this condition. But still i can give a try. One thing again comes to my mind is if the engine compression is the culprit then why should the trouble come to the surface when the engine heats up. It should be there from beginning itself.

So if the compression comes out to be correct you want to say i should go for an engine decarbonization?

After the example of your Ikon am thinking of getting another fuel pump and get it tested again.

Now this thing has become a sort of challenge to me.
Samba is offline  
Old 16th October 2013, 19:14   #21
Distinguished - BHPian
 
Samba's Avatar
 
Join Date: Apr 2013
Location: Kolkata
Posts: 2,172
Thanked: 25,396 Times
re: Trouble with my Fiat Uno Petrol. EDIT : Now Resolved!

Quote:
Originally Posted by Jaggu View Post
Just check the valve settings and springs also. Might be a long shot but worth it. Also hope you have cleared off the electricals feeding the ignition circuit for any issues.

Since it's engine knock I have a feeling it's got to do something with timing side rather than fueling.
Just checked it today. Valve settings and springs are fine.

Quote:
Originally Posted by 1100D View Post
Before invesing in a pump, hook up a fuel pipe, with fuel in a bottle held in the passenger cabin (probably as high as possible) and then try running. Infact tel l your mechanic to run the car with fuel in a bottle held high. If car runs fine, then only invest in a new fuel pump.
At last managed to do it. But still there was heavy knocking.


So after that i took my car to a different mechanic referred by one of my friend who owns a Palio. Even this guy is a experienced mechanic and he worked on Uno previously. Firstly he drove the car extensively and tried to retune the engine but in vain. At last his conclusion is he has to open the carburetor and there is a component called butterfly. According to him this butterfly has to be sent to lathe machine. I told him the carburetor is thoroughly cleaned previously but he is sure its from the butterfly of the carburetor. After visiting him while coming back the engine was going dead frequently when i was applying the clutch to stop in a signal. Once and twice the self also refused to start and it was like dead. This is the first time today the self was refusing. After 2-3 attempts the car was starting.(Not always). I called the mechanic again and told him if its fuel /carb why is the self getting dead? Self getting dead is pointing towards electrical's but according to him the the car is not getting enough fuel so the self is failing.

So what should i do, should i give a try with the carburetor butter fly in lath machine?
Samba is offline  
Old 16th October 2013, 19:47   #22
Senior - BHPian
 
1100D's Avatar
 
Join Date: Jun 2006
Location: Calcutta
Posts: 4,390
Thanked: 4,068 Times
re: Trouble with my Fiat Uno Petrol. EDIT : Now Resolved!

Quote:
Originally Posted by Samba View Post
Just checked it today. Valve settings and springs are fine.



At last managed to do it. But still there was heavy knocking.


So after that i took my car to a different mechanic referred by one of my friend who owns a Palio. Even this guy is a experienced mechanic and he worked on Uno previously. Firstly he drove the car extensively and tried to retune the engine but in vain. At last his conclusion is he has to open the carburetor and there is a component called butterfly. According to him this butterfly has to be sent to lathe machine. I told him the carburetor is thoroughly cleaned previously but he is sure its from the butterfly of the carburetor. After visiting him while coming back the engine was going dead frequently when i was applying the clutch to stop in a signal. Once and twice the self also refused to start and it was like dead. This is the first time today the self was refusing. After 2-3 attempts the car was starting.(Not always). I called the mechanic again and told him if its fuel /carb why is the self getting dead? Self getting dead is pointing towards electrical's but according to him the the car is not getting enough fuel so the self is failing.

So what should i do, should i give a try with the carburetor butter fly in lath machine?
What made him infer about the Butterfly valve? Did he check any axial play? From outside, its not possible to tell. There is a shop near Bhawanipur (a small roadside room, Shambhu, near the Gurudwara) who do Carburettors and have a setup with a competent Lathe shop to do any butterfly related work. But my guess is, since your earlier mech already cleaned the carb, he must have dismantled it, he would have definitely not have let go of the opportunity to do the Butterfly valve.
1100D is offline   (1) Thanks
Old 16th October 2013, 23:05   #23
Team-BHP Support
 
Jaggu's Avatar
 
Join Date: May 2004
Location: Bangalore
Posts: 20,207
Thanked: 15,848 Times

Quote:
Originally Posted by 1100D View Post
What made him infer about the Butterfly valve? Did he check any axial play? From outside, its not possible to tell.
-----------
But my guess is, since your earlier mech already cleaned the carb, he must have dismantled it, he would have definitely not have let go of the opportunity to do the Butterfly valve.
I think you should refer him to a good local mech any good mech can pin point such issues once they inspect it in person.

Is this the firs gen or second gen carb?
Jaggu is offline   (1) Thanks
Old 17th October 2013, 02:04   #24
Distinguished - BHPian
 
Samba's Avatar
 
Join Date: Apr 2013
Location: Kolkata
Posts: 2,172
Thanked: 25,396 Times
re: Trouble with my Fiat Uno Petrol. EDIT : Now Resolved!

Quote:
Originally Posted by Jaggu View Post
Is this the firs gen or second gen carb?
I have no idea if its a first gen or 2nd gen carb. Mostly its a 2nd gen as just few days after my car the new mpfi uno was launched with the 1.2 Liter engine. Today again i called my mechanic and asked him whether he checked the butterfly or not. According to him he checked it and its fine. Same as 1100D mentioned above. My mechanic told me he again want to change the distributor base plate and see what happens. As Magneto Merili Spares are now a days rarely available. So had to put a new Korean distributor. He told in some cases these Korean products come as faulty even when they are new. So once again when the new stock comes he will replace it and check whether its the culprit or not.

Frankly speaking my mechanic and the new mechanic i met today both are contemplating the problem on guessing as both are clue less now. None are confident on what actually is the culprit.

Anyways once my mechanic gets another set of distributor and do the needful i have no other option rather than waiting. So once its done will update here again.
Samba is offline  
Old 17th October 2013, 10:28   #25
Senior - BHPian
 
joybhowmik's Avatar
 
Join Date: Aug 2005
Location: New Delhi
Posts: 1,421
Thanked: 2,278 Times
re: Trouble with my Fiat Uno Petrol. EDIT : Now Resolved!

Quote:
Originally Posted by Samba View Post
Frankly speaking my mechanic and the new mechanic i met today both are contemplating the problem on guessing as both are clue less now. None are confident on what actually is the culprit.
At the risk of sounding completely - did you check the air-filter?

I cannot offer up a solution to the problem , but thought to summarize the background, symptoms , actions and planned actions, so that it is clearly visible in one post. That may help someone on the forum offer a solution.

Symptoms:
While slowing down car - engine dies
Power loss on level road (50 kmph in 5th gear)
Power loss when going up typical urban slope (flyover)
Power loss increases on warm running
car starts with heavy knocking
No white smoke
No decrease in engine oil level


Background:
13 yo car on stock components, well maintained
New clutch
Exide Battery 8 months old
Engine oil changed recently
Engine oil fileter changed recently
Fuel quality is good - confirmed


Actions so far:
Cleaned Fuel lines
Cleaned carbureter jet
Cleaned/Serviced Carburetor
Checked Carburettor Butterfly valve
Checked/Cleaned intake manifold
Checked vaccum advance
Checked ignition timing
Replaced fuel pump - problem persists
Cleaned fuel pipes
Retuned engine
Changed ignition coil
Changed distributor
Changed spark plugs/plug wires
Checked valve settings/springs

Planned Actions:
Replace Distributor as earlier replacement is suspect.
Compression test on the cylinders
Engine decarbonization
joybhowmik is offline   (2) Thanks
Old 17th October 2013, 10:49   #26
Team-BHP Support
 
Jaggu's Avatar
 
Join Date: May 2004
Location: Bangalore
Posts: 20,207
Thanked: 15,848 Times
re: Trouble with my Fiat Uno Petrol. EDIT : Now Resolved!

Quote:
Originally Posted by Samba View Post
He told in some cases these Korean products come as faulty even when they are new. So once again when the new stock comes he will replace it and check whether its the culprit or not.
Can be this or the install is not correct?

Quote:
Originally Posted by joybhowmik View Post
Engine decarbonization
I would suggest against this, if it is done using those decarb machines. In an old engine it will dislodge carbon and can create bigger issues including frequent plug fouling etc. If its traditional decarb by dismantling the heads, its ok.
Jaggu is offline   (1) Thanks
Old 17th October 2013, 11:16   #27
Senior - BHPian
 
bj96's Avatar
 
Join Date: Dec 2008
Location: Pune
Posts: 1,039
Thanked: 1,323 Times
re: Trouble with my Fiat Uno Petrol. EDIT : Now Resolved!

Quote:
Originally Posted by joybhowmik View Post
...
Power loss on level road (50 kmph in 5th gear)
Power loss when going up typical urban slope (flyover)
Power loss increases on warm running
...
In an earlier post you also mention of a very low mileage. Can the clutch be a suspect? I saw you have new clutch, but, if Uno has a cable actuated clutch, cable may be too tight causing it to slip on load.

-BJ

Last edited by bj96 : 17th October 2013 at 11:18. Reason: clutch ref
bj96 is offline   (1) Thanks
Old 17th October 2013, 19:17   #28
Distinguished - BHPian
 
Samba's Avatar
 
Join Date: Apr 2013
Location: Kolkata
Posts: 2,172
Thanked: 25,396 Times
re: Trouble with my Fiat Uno Petrol. EDIT : Now Resolved!

Quote:
Originally Posted by joybhowmik View Post
At the risk of sounding completely - did you check the air-filter?
I have changed the air filter too.

Quote:
Originally Posted by bj96 View Post
In an earlier post you also mention of a very low mileage. Can the clutch be a suspect? I saw you have new clutch, but, if Uno has a cable actuated clutch, cable may be too tight causing it to slip on load.

-BJ
Uno has a hydraulic clutch. There is no problem with the clutch plate. We have checked it. Actually the engine is knocking while in neutral also while idling. That means clutch is not the issue.

Quote:
Originally Posted by Jaggu View Post
Can be this or the install is not correct?
Yes the installation is correct he checked it twice.

My next course of actions-
1) Will check with distributor once again.
2)If the problem still persists will go for the butterfly valve lathe.
3) Still if its not solved will get the engine compression test done.
4) If test result is fine will get the engine decarbonized and if the engine compression result comes out negative then i have no option left rather than doing a reboring!

Last edited by Samba : 17th October 2013 at 19:24.
Samba is offline  
Old 17th October 2013, 19:39   #29
Senior - BHPian
 
joybhowmik's Avatar
 
Join Date: Aug 2005
Location: New Delhi
Posts: 1,421
Thanked: 2,278 Times
re: Trouble with my Fiat Uno Petrol. EDIT : Now Resolved!

Quote:
Originally Posted by Samba View Post
If test result is fine will get the engine decarbonized and if the engine compression result comes out negative then i have no option left rather than doing a reboring!
I think, given what you have described so far, taking the head off and inspecting the block is the last resort.
There too, see if fitting rings on the piston solves the issue rather than reboring the cylinders.
joybhowmik is offline   (1) Thanks
Old 17th October 2013, 19:46   #30
Senior - BHPian
 
joybhowmik's Avatar
 
Join Date: Aug 2005
Location: New Delhi
Posts: 1,421
Thanked: 2,278 Times
re: Trouble with my Fiat Uno Petrol. EDIT : Now Resolved!

Quote:
Originally Posted by Samba View Post
Once and twice the self also refused to start and it was like dead. This is the first time today the self was refusing. After 2-3 attempts the car was starting.(Not always). I called the mechanic again and told him if its fuel /carb why is the self getting dead? Self getting dead is pointing towards electrical's but according to him the the car is not getting enough fuel so the self is failing.
I missed this point in my list above. Can you also do an ampere reading on the self when engine is warm and when engine is cold? Just to rule out the obvious.
joybhowmik is offline   (1) Thanks
Reply

Most Viewed
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Copyright ©2000 - 2024, Team-BHP.com
Proudly powered by E2E Networks