Team-BHP > Technical Stuff
Register New Topics New Posts Top Thanked Team-BHP FAQ


Reply
  Search this Thread
122,987 views
Old 5th November 2013, 15:17   #1
Distinguished - BHPian
 
SS-Traveller's Avatar
 
Join Date: Jan 2009
Location: New Delhi
Posts: 8,164
Thanked: 27,143 Times
Underbody Hit & Cracked Sump : Implications, Vulnerabilities, Responsibilities

Rocky roads are wonderful when they're served on your plate...
Underbody Hit & Cracked Sump : Implications, Vulnerabilities, Responsibilities-rockyroad1024x682.jpg

...or as off-roading challenges...


...but certainly not when you are faced with them while driving along in your hatchback or sedan.
Underbody Hit & Cracked Sump : Implications, Vulnerabilities, Responsibilities-rockypathblackwhite878732.jpg

It is actually shocking how many folks damage their sumps while driving, allow all the oil to drain out, and wind up with terminal damage to their engines. The expense, running into six figures, needs to be, more often than not, paid out of one's own pocket because
- manufacturers' warranty does not cover user-caused damage, and
- insurance companies either refuse to pay up in full, or not at all, citing design defects by the manufacturer, or consequential damage waiver clauses in the policy document.

Just to give you an idea of how many people report cracked sumps and resultant burnt engines on Team-BHP, click on this link.

Last edited by SS-Traveller : 5th November 2013 at 16:49.
SS-Traveller is offline   (36) Thanks
Old 5th November 2013, 16:48   #2
Distinguished - BHPian
 
SS-Traveller's Avatar
 
Join Date: Jan 2009
Location: New Delhi
Posts: 8,164
Thanked: 27,143 Times
Re: Underbody Hit & Cracked Sump : Implications, Vulnerabilities, Responsibilities

Certain cars are more vulnerable than others, due to their abysmally low ground clearance, exactly where the sump is located. This has to do with design, and there's not a lot that you and I as the owner can do about it. Some manufacturers add a steel bash plate or protection plate under the sump, just to protect against the eventuality of a cracked sump, and then there are other cars where it is not feasible to fix such a plate.

Beware of the plastic protection plate that looks solid but provides as much protection to your sump, as a cocktail umbrella does to you in pouring rain. Some SUVs such as the XUV500 do have such plastic sump guards, but that is more to reduce ground-clearance-based taxes, and do nothing to protect the sump (the XUV500's sump has plenty of clearance below it anyway).

The following list is by no means comprehensive, but points out some of the cars that are prone to taking underbody hits and breaking their sumps when negotiating not-too-big rocks or bumps on the road.Please feel free to share your experiences of sump damage and the specific model of car you drive, on this thread.

Last edited by SS-Traveller : 6th November 2013 at 11:17.
SS-Traveller is offline   (23) Thanks
Old 5th November 2013, 17:22   #3
Distinguished - BHPian
 
SS-Traveller's Avatar
 
Join Date: Jan 2009
Location: New Delhi
Posts: 8,164
Thanked: 27,143 Times
Re: Underbody Hit & Cracked Sump : Implications, Vulnerabilities, Responsibilities

So what can be done to minimize your chances of getting a cracked sump, and even worse, a seized engine?

When choosing a car to buy
Check below the car from the front and rear ends to determine which are the lowermost points, and how close they are to the ground. If you cannot identify any component, and think it is closer to the ground than the thickness of 2 bricks placed one over the other, get someone knowledgeable to check and determine what it is. Look for the presence of a engine protection plate, made of steel, that prevents the sump from being punctured or cracked.

The underside of the sump is the most vulnerable, and so is the gearbox and differential. Drain nuts on the sump/gearbox/differential are especially vulnerable if they are positioned at the lowermost point and are unprotected. Certain components of the suspension can be pretty tough and survive heavy knocks, even if they hit a stone on the road while driving.

While driving
  • Don't follow too close behind a high-GC vehicle, like a truck. It can go over a rock, which can damage your low-GC car when you run over it without warning. Leaving a safe distance will allow you space to brake or dodge around that obstacle.
  • Negotiate large speed breakers with care. Read about how to do it on this thread.
Once the damage is done


STOP THE CAR!
Once you hear that sickening *CRUNCH*, *THUD* or *BANG* from under the car, pull in by the side of the road immediately (with heavy oil loss, your engine will suffer expensive damage in 30 seconds or less). Do not accelerate. Try to shift to neutral as quickly as possible, turn off the engine (but do not pull out the ignition key), and coast to a stop. Get under the car and assess the extent of damage. If there is any oil leak, do not attempt to start the engine again until the leak is fixed and the lost oil topped up.

Temporary repairs to get you back on the road
Extensive damage to the sump cannot be temporarily repaired, and the only option you have is to have the car towed to a nearby garage or ASC.

Small cracks or holes on the sump can be plugged temporarily using one of the following:
  • Epoxy resin putty (e.g. M-Seal, QuikSteel, Loctite)
  • A mix of carbolic soap (e.g. Lifebuoy) and sugar crystals
  • Chewing gum (not very effective)
Top up with ANY engine oil available at the nearest petrol pump or automobile spares shop - there is no need to be finicky. Even if it is a monograde mineral oil and not your favourite multigrade synthetic oil, it will still lubricate your engine well enough to let you drive to the next service station without your engine self-destructing.

Finally settling the issue...
Most ASCs will advise you to replace the sump. If it is a steel sump and the damage is minimal, removing the sump, hammering out the dent and welding the hole is going to work as well as replacing the whole unit. OTOH, aluminium sumps are more difficult to repair, and brass brazing in expert hands usually produces good results - if in doubt, change the sump. Also check for impact marks on other components such as the suspension arms, and rectify as required.

In the unfortunate event that the engine suffers extensive damage, the likelihood of your ASC or the insurance company footing the bill is pretty bleak. The best you can expect is perhaps 50% reimbursement - it would be your lucky day if you do manage to get the whole bill reimbursed. The standard excuses include:
  • Consequential damage to engine, not directly as a result of the accident. Insurance company agrees to pay for sump replacement only;
  • User damage, not covered under warranty;
  • Insurance company claims that not having an engine protection plate is a manufacturing defect, and manufacturer is liable to pay for damage.
Rebuilding a burnt engine is always cheaper if done at an FNG, but then obviously not many are keen to trust an FNG instead of the authorized service centre.

FINAL WARNING: Rocks on the road can substantially lighten your pocket.

Last edited by Rudra Sen : 6th November 2013 at 16:14. Reason: Corrected with to without.
SS-Traveller is offline   (51) Thanks
Old 6th November 2013, 13:18   #4
Team-BHP Support
 
bblost's Avatar
 
Join Date: Jul 2007
Location: Hyderabad
Posts: 11,008
Thanked: 15,352 Times
Re: Underbody Hit & Cracked Sump : Implications, Vulnerabilities, Responsibilities

Thread moved from Assembly Line.

Thanks for sharing.
bblost is offline  
Old 6th November 2013, 13:51   #5
Senior - BHPian
 
tanwaramit's Avatar
 
Join Date: Aug 2005
Location: Dilwalon ki Dilli
Posts: 1,930
Thanked: 497 Times
Re: Underbody Hit & Cracked Sump : Implications, Vulnerabilities, Responsibilities

thats a very good and informative thread SST, with the recent case of Polo as reported here.

two concerns.

1. What to do in case of heavy rains? One may not see the rock on the road and getting out and checking for oil leak may not be that practical.
2. In case of oil leak there should be some indicator on the dashboard which should warn the driver of the leak.
tanwaramit is offline   (2) Thanks
Old 6th November 2013, 14:15   #6
Distinguished - BHPian
 
Join Date: May 2013
Location: Bengaluru
Posts: 1,796
Thanked: 7,789 Times
Re: Underbody Hit & Cracked Sump : Implications, Vulnerabilities, Responsibilities

Thank you very much for this very informative post. Looking at many threads in past few weeks, this seems to be well timed and informed. One must learn to baby the car over all bad stretches and patience pays in this situation.

A quick question though -

Quote:
Originally Posted by SS-Traveller View Post
STOP THE CAR!
....Try to shift to neutral as quickly as possible, turn off the engine (but do not pull out the ignition key), and coast to a stop....
Why do you recommend not to pull the ignition key out? Not sure if I misunderstood it?

And another one - while running on under construction road, the stones that gets tossed under belly due to mediocre speeds or other vehicles (stones of size say 5-7cms in width) can cause similar damage? Often in the under construction roads, trucks ply beside the cars and such stones get tossed up. Rare but if its underbelly, it should be fine I guess as the speeds will be relatively slow?
abirnale is online now  
Old 6th November 2013, 14:51   #7
BHPian
 
Babuda's Avatar
 
Join Date: Aug 2013
Location: Kolkata
Posts: 108
Thanked: 108 Times
Re: Underbody Hit & Cracked Sump : Implications, Vulnerabilities, Responsibilities

Quote:
Originally Posted by abirnale View Post

A quick question though -

Why do you recommend not to pull the ignition key out? Not sure if I misunderstood it?
Removing the ignition key will result in the steering getting locked = no directional control.
Babuda is offline   (6) Thanks
Old 6th November 2013, 15:34   #8
Senior - BHPian
 
phamilyman's Avatar
 
Join Date: Jul 2007
Location: Gurgaon
Posts: 5,968
Thanked: 4,642 Times
Re: Underbody Hit & Cracked Sump : Implications, Vulnerabilities, Responsibilities

Quote:
Originally Posted by SS-Traveller View Post
Top up with ANY engine oil available at the nearest petrol pump or automobile spares shop - there is no need to be finicky. Even if it is a monograde mineral oil and not your favourite multigrade synthetic oil, it will still lubricate your engine well enough to let you drive to the next service station with your engine self-destructing.
As someone who lost a turbo to broken uttarakhand roads (and saw four others do the same), I have to say that this is COMPLETELY wrong esp in most diesel engines.

The only solution like you said upfront, is to coast to a stop, and just tow the car. Most folks have no idea of knowing what has already gone wrong (over and above the check engine light) after such an impact.

Your only option is a fancy flat bed tow truck, or the bolero from the local taxi stand (which isnt really bad IME).

My side recommendation is to ask upfront about spare part costs -did anyone know that a Sunny turbocharger costs 1.1 lakh (+taxes, AFAIK) while SX4 turbo is 35k all inclusive?

Hence for someone who tours often on all sorts of terrain, one needs to choose his/her car wisely. This was one solid reason which kept me back from buying a Sunny when the swift was beginning to show its age (its another fact that circumstances forced a postponement of the new car purchase!).
phamilyman is offline   (2) Thanks
Old 6th November 2013, 17:29   #9
Team-BHP Support
 
tsk1979's Avatar
 
Join Date: Feb 2005
Location: San Jose, CA
Posts: 23,717
Thanked: 22,825 Times
Re: Underbody Hit & Cracked Sump : Implications, Vulnerabilities, Responsibilities

Quote:
Originally Posted by phamilyman View Post
As someone who lost a turbo to broken uttarakhand roads (and saw four others do the same), I have to say that this is COMPLETELY wrong esp in most diesel engines..
Why is this wrong.
In case of major damage to sump with engine oil flowing out at speed you are right.
However, if you can patch up the sump so that its only 1-2 drops falling out at a time, you can top up the car, and drive for a 100km or so.
Think of it as a car which is leaking some oil. As long as there is enough oil available, its fine.
That said, a rock hit at speed will cause major damage, not small patch damage unless the under sump skid plate has taken the brunt of the impact.
tsk1979 is offline   (1) Thanks
Old 6th November 2013, 19:41   #10
Distinguished - BHPian
 
dhanushs's Avatar
 
Join Date: Oct 2009
Location: Chennai
Posts: 4,282
Thanked: 10,180 Times
Re: Underbody Hit & Cracked Sump : Implications, Vulnerabilities, Responsibilities

Quote:
Originally Posted by SS-Traveller View Post
.... While driving..
IMO, In this case, the most important thing to follow while driving is to keep a keen eye on the instrument console, for the oil pressure gauge, or the oil warning light. Without which most people end up with a bust engine.
Quote:
Originally Posted by phamilyman View Post
I have to say that this is COMPLETELY wrong esp in most diesel engines.
Not really. There is no need for synthetic oils to run short intervals. Only the correct or atleast near-correct grade for ~50-100 or so kilometers, by which hopefully, you can find a patch up garage (Removing/replacing/repairing the crank-case is very easy) and a proper oil. IMO, most turbos should survive.

And, I'd advice not to revv the engine really high in this interval, and to baby it. Load is OK, but rpms = absolute NO.
dhanushs is offline   (1) Thanks
Old 6th November 2013, 21:51   #11
Distinguished - BHPian
 
SS-Traveller's Avatar
 
Join Date: Jan 2009
Location: New Delhi
Posts: 8,164
Thanked: 27,143 Times
Re: Underbody Hit & Cracked Sump : Implications, Vulnerabilities, Responsibilities

Quote:
Originally Posted by tanwaramit View Post
1. What to do in case of heavy rains? One may not see the rock on the road and getting out and checking for oil leak may not be that practical.
Amit, I'd rather endure wet and muddy clothes (even if they're expensive clothes), than a 6-figure bill to fix a bust engine. One may not see the rock on the road all right, but after a hit, getting out to check for oil leaks is quite doable.
Quote:
Originally Posted by abirnale View Post
Why do you recommend not to pull the ignition key out? Not sure if I misunderstood it?

And another one - while running on under construction road, the stones that gets tossed under belly due to mediocre speeds or other vehicles (stones of size say 5-7cms in width) can cause similar damage? Often in the under construction roads, trucks ply beside the cars and such stones get tossed up. Rare but if its underbelly, it should be fine I guess as the speeds will be relatively slow?
Babuda has already explained why the key shouldn't be pulled out of the ignition - thanks, Babuda.

Gravel and stones ejected from tyres can break glass, and even puncture metal (I've experienced a broken window glass from a stone ejected by a truck tyre). If you are running at high speeds on a gravelly road, and your luck runs out, well, you can puncture your sump too (I've seen someone's radiator punctured by another gravel bit ejected by a truck tyre).
Quote:
Originally Posted by phamilyman View Post
...I have to say that this is COMPLETELY wrong esp in most diesel engines.

The only solution like you said upfront, is to coast to a stop, and just tow the car. Most folks have no idea of knowing what has already gone wrong (over and above the check engine light) after such an impact.

Your only option is a fancy flat bed tow truck, or the bolero from the local taxi stand (which isnt really bad IME).
Oh, come on, Hitanshu. For a 100 km, any (genuine) oil of whatever grade will keep your engine intact - provided the damage hasn't occurred already after the leak. I'd think Tanveer and Dhanush have responded to your opinion adequately - thank you both for explaining this.
Quote:
Originally Posted by phamilyman View Post
My side recommendation is to ask upfront about spare part costs -did anyone know that a Sunny turbocharger costs 1.1 lakh (+taxes, AFAIK) while SX4 turbo is 35k all inclusive?
Once again, I'd think this is a bit far-fetched - choosing a new car based on TC cost is probably the last thing I'd do, in anticipation of an engine burnout event.
Quote:
Originally Posted by tanwaramit View Post
2. In case of oil leak there should be some indicator on the dashboard which should warn the driver of the leak.
Quote:
Originally Posted by dhanushs View Post
IMO, In this case, the most important thing to follow while driving is to keep a keen eye on the instrument console, for the oil pressure gauge, or the oil warning light. Without which most people end up with a bust engine.
The oil pressure indicator light is there in all cars. But depending on that to light up means there's got to be almost complete loss of oil pressure in the gallery. Well before that, components like crankshaft bearings, which depend on splash lubrication, would have run dry, with resultant damage and expense. Therefore, after an oil sump hit, it's best to check as early as possible if the car is losing oil.
SS-Traveller is offline   (1) Thanks
Old 6th November 2013, 22:02   #12
Senior - BHPian
 
Join Date: Jul 2009
Location: Calcutta
Posts: 4,668
Thanked: 6,217 Times
Re: Underbody Hit & Cracked Sump : Implications, Vulnerabilities, Responsibilities

Quote:
Originally Posted by phamilyman View Post
As someone who lost a turbo to broken uttarakhand roads (and saw four others do the same),
Five people loosing their turbos! Details of this should be interesting.

Quote:
Originally Posted by SS-Traveller View Post
Well before that, components like crankshaft bearings, which depend on splash lubrication, would have run dry,
??

Regards
Sutripta
Sutripta is offline  
Old 6th November 2013, 22:07   #13
Distinguished - BHPian
 
SS-Traveller's Avatar
 
Join Date: Jan 2009
Location: New Delhi
Posts: 8,164
Thanked: 27,143 Times
Re: Underbody Hit & Cracked Sump : Implications, Vulnerabilities, Responsibilities

Quote:
Originally Posted by Sutripta View Post
??
Qualifier to be added - On some engines...
SS-Traveller is offline  
Old 6th November 2013, 23:35   #14
BHPian
 
pdma's Avatar
 
Join Date: Oct 2013
Location: Hyderabad
Posts: 617
Thanked: 917 Times
Re: Underbody Hit & Cracked Sump : Implications, Vulnerabilities, Responsibilities

Quote:
Originally Posted by SS-Traveller View Post

The oil pressure indicator light is there in all cars. But depending on that to light up means there's got to be almost complete loss of oil pressure in the gallery. Well before that, components like crankshaft bearings, which depend on splash lubrication, would have run dry, with resultant damage and expense. Therefore, after an oil sump hit, it's best to check as early as possible if the car is losing oil.
This is very useful information and an apt thread at this period where most of the roads in India have taken a beating due the recent monsoon.
I definitely agree to the point that clothes are much much cheaper then dealing with an engine seizure.
Also as a practice I suggest we carry a torch light in the boot which will be very handy in these situations specially when the sun is down.
I always have a torch , an umbrella, a bottle of water & some pieces of cloth placed in my car's boot all the time and each one of them had a chance to show their usefulness at some point or the other .
pdma is offline   (2) Thanks
Old 7th November 2013, 01:51   #15
BHPian
 
Join Date: Jan 2010
Location: Chennai
Posts: 420
Thanked: 137 Times
Re: Underbody Hit & Cracked Sump : Implications, Vulnerabilities, Responsibilities

So which cars / SUV, according to you, protect the sump plate the best?
acidkill is offline  
Reply

Most Viewed


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