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  •  » exhaust smell

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    5/08/2013 8:40 AM  #1

    mark1965
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    Registered: 4/03/2013
    Posts: 172

    exhaust smell

    65 coupe with 1980 302 the car has hi pro manifold h pipe 40 ser delta flows and the pipes exit in the rear all joints are welded solid but i still have an exhaust smell in the car . i noticed on the back of the heads there are two holes one on each head i think they are for a heat riser to the old carb maybe i have them plugged now but my question is are they for heat only or exhaust as well. iam thinking that may be where my smell is comming from. any ideas on how to find a leak?

     

    5/08/2013 9:27 AM  #2

    GPatrick
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    Re: exhaust smell

    Those are probably EGR ports and yes, they need to be plugged.  Uncaptured oil vapor can produce a smell that can be mistaken for exhaust.  What are you using for crankcase ventillation?  A PCV valve on one valve cover and vented cap on the other generally controls the vapor and smells but a stuck PCV or a valve cover without a baffle may pull excessive oil and lead to some smells.  A slight valve cover leak can cause drips on hot manifolds.  From what I understand from older posts, a faulty/worn trunk seal can allow fumes to be sucked into the passenger compartment even when the exhaust system is properly sealed.  Inspect your seal and replace if worn.   Check all joints in your exhaust - manifold/header to pipe, pipe to inlet/outlet of muffler, etc.  Might be easier to do if you can get the car on a lift and check it while running.  Does this seem to be a problem when sitting at idle or when driving?

     

    5/08/2013 9:37 AM  #3

    MS
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    From: Canyon Lake, Texas
    Registered: 1/24/2013
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    Re: exhaust smell

    Thos holes in the heads exist in the front and rear of the heads.  They need to be plugged with a thermactor plug.  The front ones are typically used to mount the a/c, power steering or alternator to the heads, so a special plug is made for that.  It has 5/8" threads on the OD and 3/8" on the ID.  The end is tapered so it seals the holes.  The picture shows a set.  They are available at lots of places, but google THERMACTOR PLUGS and do some shopping because prices vary widely.  Jegs and Summit have them, as does your local Ford dealer.  Cheaper places like RockAuto probably carry as well for less.  In a pinch, a 5/8" coarse thread bolt will work in the ones on the rear of the heads.  The holes go straight into the exhaust ports, so they need to be filled.

    Money you enjoy wasting is NOT wasted money... unless your wife finds out.
     

    5/08/2013 11:29 AM  #4

    josh-kebob
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    From: Madison, AL
    Registered: 4/06/2013
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    Re: exhaust smell

    how far past your rear valance do your exhaust tips extend?
    what's the condition of your deck lid gasket?

     

    5/08/2013 11:37 AM  #5

    mark1965
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    Re: exhaust smell

    josh-kebob wrote:

    how far past your rear valance do your exhaust tips extend?
    what's the condition of your deck lid gasket?

    about 3"
     

       •Thread Starter
     

    5/08/2013 11:39 AM  #6

    mark1965
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    Re: exhaust smell

    GPatrick wrote:

    Those are probably EGR ports and yes, they need to be plugged.  Uncaptured oil vapor can produce a smell that can be mistaken for exhaust.  What are you using for crankcase ventillation?  A PCV valve on one valve cover and vented cap on the other generally controls the vapor and smells but a stuck PCV or a valve cover without a baffle may pull excessive oil and lead to some smells.  A slight valve cover leak can cause drips on hot manifolds.  From what I understand from older posts, a faulty/worn trunk seal can allow fumes to be sucked into the passenger compartment even when the exhaust system is properly sealed.  Inspect your seal and replace if worn.   Check all joints in your exhaust - manifold/header to pipe, pipe to inlet/outlet of muffler, etc.  Might be easier to do if you can get the car on a lift and check it while running.  Does this seem to be a problem when sitting at idle or when driving?

     THE SMELL IS MORE NOTICABLE AFTER RUNNING AND COMMING TO A STOP BUT YOU CAN SMELL IT WHEN YOUR UP TO SPEED

       •Thread Starter
     

    5/08/2013 1:17 PM  #7

    GPatrick
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    Re: exhaust smell

    I'd probably start with the trunk seal/gasket and see if that helps.  If the gasket is new, it does not mean that it seals well if it is not Scott Drake (as suggested on this site).  But, an extended run and then a stop is also a symptom of an oil leak - the long run time produces more leakage and then you smell it when you stop.  A strong exhaust smell may also simply be a symptom of an overly rich mixture - either idle or mains.  Start with oil leak checks (also check transmission output seal/yoke leaks that can spray onto pipes and pinion seal) and the trunk gasket.

     

    5/09/2013 8:05 AM  #8

    BobN
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    Re: exhaust smell

    The thermactor plugs are what is supposed to be used to plug the holes in the back of the head, but I have always used an old spark plug. It is the same thread and can be found for free. Just break off the ceramic end and screw it in.

    I just saved you $5 and no one will ever see it.


    BobN

     

    5/09/2013 2:05 PM  #9

    MS
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    From: Canyon Lake, Texas
    Registered: 1/24/2013
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    Re: exhaust smell

    BobN wrote:

    The thermactor plugs are what is supposed to be used to plug the holes in the back of the head, but I have always used an old spark plug. It is the same thread and can be found for free. Just break off the ceramic end and screw it in.

    I just saved you $5 and no one will ever see it.


    BobN

     What spark plugs have 5/8" coarse threads?

    Money you enjoy wasting is NOT wasted money... unless your wife finds out.
     

    5/10/2013 12:09 PM  #10

    BobN
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    Re: exhaust smell

    14mm sparkplug that would be used on a latemodel stock head with a cone seat screws in just fine and I have done that on several sets of heads for over 10 years now. It could well be that they don't match the thread perfectly, but they screw in easy and once they bottom out they don't fall out and stay put. I have used them on iron and aluminum heads.

    BobN

     

    5/10/2013 5:23 PM  #11

    6sally6
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    From: Surfside Beach,SC
    Registered: 4/02/2013
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    Re: exhaust smell

    BobN wrote:

    14mm sparkplug that would be used on a latemodel stock head with a cone seat screws in just fine and I have done that on several sets of heads for over 10 years now. It could well be that they don't match the thread perfectly, but they screw in easy and once they bottom out they don't fall out and stay put. I have used them on iron and aluminum heads.

    BobN

     
    Shoot!! Ain't nuth'in a BFH won't fix!
     

    Get busy Liv'in or get busy Die'n....Host of the 2020 Bash at the Beach/The only Bash that got cancelled  )8
     

    5/10/2013 5:25 PM  #12

    6sally6
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    Re: exhaust smell

    Let me add this to the OP.   If its "all-cammed-up" its gonna need a bunch of initial timing. That will help/fix the rich burning at idle and low speed.
    6sallly6

    Get busy Liv'in or get busy Die'n....Host of the 2020 Bash at the Beach/The only Bash that got cancelled  )8
     

     

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