Engine & Gearbox Coolant smell but no obvious leaks

Discussion in '6th Generation (1997-2002)' started by philoldsmobile, Wednesday 8th May, 2013.

  1. philoldsmobile Club Member ★ ☆ ☆ ☆ ☆

    Hi guys,

    Ever since I bought it my 2002 accord has had a faint smell of coolant when its hot (worse after a town run) It never drops coolant on the floor, and has only needed topping up about three times in 7000 miles about a liter in total. Are there any areas these engines are known to leak from? the car had a new rad in 2010 and I can't see any obvious degradation or leaks, so I am wondering if the spring hose clamps have gone a little weak (had this on my old celica, cured with jubilee clips)

    Any thoughts?
     
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  2. Roylewaa Club Member ★ ☆ ☆ ☆ ☆

    Funny as I noticed this on mine on Monday as me and the family went to the park and we were sitting on a blanky in front of the car and the Mrs noticed the smell first and when I sniffed the grille area I could smell what smells like burning coolant, I have no obvious leaks and the level is on max in the expansion bottle. Weird:Blink:
     
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  3. GarymandingAccord Junior Member ☆ ☆ ☆ ☆ ☆

    Check for leaks from the heater matrix, usually in a box behind the dash. It may be leaking into the cabin so check the front foot wells for dampness as this could be a sure sign.
     
  4. SpeedyGee Administrator Staff Team

    England Speedy Birmingham
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    Also check your radiator cap is good condition. If this is failing it will spew coolant over the radiator instead of sucking it in and pushing it out to the expansion bottle.
     
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  5. wumps Junior Member ★ ☆ ☆ ☆ ☆

    i would go with check the heater matrix had a few of those go on various cars over the years
     
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  6. philoldsmobile Club Member ★ ☆ ☆ ☆ ☆

    heater matrix is good, no smell or wetness inside the car, only the slight (and it is slight) smell outside. The rad cap is a good call, there is no obvious sign of it leaking, but its possible its venting just the tiniest amount.
     
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  7. Beefy Expert Advisor ★ ★ ★ ★ ★

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    Have your coolant system pressure tested bud. If there is a leak you should find it then.
     
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  8. Ichiban Founder Staff Team

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    Check the lower end of the radiator they are prone to the elements ,it the fist place the cooling fin get battered exposing the matrix veins you may have a small fracture causing the leak then evaporation causing the smell. additionally check the rubber hose where the clamps are for rubber cracking ,Temperature sensor for leaks & lastly the lower rad drain plug. A pressure test will pin point the leak soon.
     
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  9. philoldsmobile Club Member ★ ☆ ☆ ☆ ☆

    I do wonder if im over filling it too, Usually the upper mark is full hot, but as its just a line I assumed its full cold. fill it to the line and it looses it quickly, let it drop down and it seems to not loose much at all (if anything) Where do people fill them to? I must admit, I had considered the radiator as it is a little exposed, and there is stone damage to some of the fins.
     
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  10. Ichiban Founder Staff Team

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    In Coolant in the expansion bottle should be at the top level when the engine is bone cold.
     
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  11. Ichiban Founder Staff Team

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    Phil any new developments bud?
     
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  12. philoldsmobile Club Member ★ ☆ ☆ ☆ ☆

    I had a hunt around again this evening, there are two minor suspects, the stat housing is slightly damp, but i can't see if its oil from somewhere else (though no obvious oil leaks, and no oil usage at all) or water, and possibly the rad, as its surprisingly stone damaged for a 3 year old radiator. The usage is very slight, perhaps 250ml per month, if not less (I do about 2000 miles a month) so i'm going to chuck a bottle of K seal in as I have had excellent results with it in my old Alfa Romeo in the past (the Alfa 166 heater matrix is prone to leaking and misting up the inside of the windscreen) I threw K seal in the alfa and the leak and water use stopped. It was still perfect 2 years and 20,000 miles later when I sold the car.

    I do think the rad may be the problem as its worse around town when the rad works harder. After my 50 mile (each way) motorway commute there is little to no coolant smell at all. Its got no worse since I bought the car six months ago either. I have seen a couple of instances where rads have been faulty and seeped coolant from the crimp joint between the rad and side tanks from new. This can be very hard to detect if the leak is hidden from view..
     
    Last edited: Friday 10th May, 2013
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  13. Ichiban Founder Staff Team

    England CJ Leeds
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    Pressure test? you know anyone close to you who has one you could borrow?
     
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  14. philoldsmobile Club Member ★ ☆ ☆ ☆ ☆

    Just had a message from a previous owner (and honda specialist) who diagnosed the problem when the previous owner had the car. Apparently there is a steel coolant pipe between the water pump and the thermostat housing, and the weld rusts - mine was leaking from there when he looked at it in the previous owners hands. The previous owner put radweld in and the leak stopped. As Hondaman seem to have a good reputation Ill get the car up to him very soon for the coolant pipe and an EGR passage clean out.
     
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