Pump Fuel Stink?

[gungeey]

Not sure where I got these

 

Mc S4010 

They have steel sandwiched in the middle

[gungeey]

Here

[XframeFX]

4 minutes ago, gungeey said:

They have steel sandwiched in the middle

Ah, much appreciated!

Now THOSE are real gaskets and would be most suitable with that plate if exhaust holes were open.

I still prefer it without the plate and holes plugged. TX!

[gungeey]

2 minutes ago, XframeFX said:

without the plate and holes plugged. 

That is what I do 👍 

[telriv]

That is also what I do & recommend on all.

BUT, IF you don't plug the holes you need the plate to keep the aluminum bottom of the carb. from getting  "Eaten" away from the exhaust.

 

Tom T.

[XframeFX]

I am bringing this back after PMing with Tom T.

 

I installed the new T/A Performance aluminum intake last week and still with the original AFB. Reason? It has a spreadbore flange. So, I'm giving the AFB one last chance to redeem itself. If still NG, I can now switch to a more refined Rochester 4MV Q-Jet.

 

However, as of recent, attention is back on exhaust valve seat inserts. One of my symptoms is considerable condensation out the tailpipes. The other is that stink! It is not sweet, rotten eggs, raw or burnt fuel. Just a vial odor. No smoke either.

There is lots on various forums on valve seat inserts. But, nothing on symptoms. Do they leak coolant, show up on compression or leak down tests, smell, pop out and catastrophic failure?

I thought failure mode of inserts was during machining or during startup, not manifest itself after 30 years?. So far, nothing discreet. All cylinder temps/compression appear equal.

 

I know Carmen F. has successfully installed them long ago. One Forum regular, also with a '63 has exhaust valve seat inserts. Anyone else with these inserts? Long term success?

 

Aluminum dual plane spreadbore Intake (yes, it clears the hood):

 

 

 

 

Edited May 28 by XframeFX (see edit history)

[EmTee]

It sure does look fast! 

[XframeFX]

5 hours ago, EmTee said:

It sure does look fast!

I left off the cross bracket from the top front of the A6 Compressor. It did reach the threaded hole on the intake but no room to slip it under the rear bracket.

 

FYI for anyone considering this Intake. It's 15 lbs, it all bolts-up after shimming with one thick washer on 2 of 3 holes on the rear of the A6 compressor. Also, plugging three 1/8-27 NPT ports. Routing the 5/8 heater hose kinked slightly even with the old cast iron battleship (Lime arrow). Probably hose is too long.

Thought this intake would produce anther kink with an unnecessary mounting boss at the rear (Blue arrow), all good though. Red arrow shows threaded hole for the A6 rear bracket 5 cm further to the rear.

 

 

[EmTee]

15 hours ago, XframeFX said:

However, as of recent, attention is back on exhaust valve seat inserts. One of my symptoms is considerable condensation out the tailpipes. The other is that stink! It is not sweet, rotten eggs, raw or burnt fuel. Just a vial odor. No smoke either.

If a valve seat penetrated the water jacket allowing coolant to seep into the combustion chamber (esp. after shutdown) it seems to me that the one unavoidable consequence would be a steady loss of coolant.  Do you have to keep topping-off the radiator?  I think the water that you see at cold startup is most likely condensation.  Could the smell be caused by acids in that water collected in the exhaust system attacking the metal; particularly the plating or galvanized coatings?  Is the exhaust system stainless steel, or coated mild steel?

 

Have you pressure-tested the cooling system recently?  If the cooling system holds pressure for say, an hour, then you can be pretty sure you don't have an issue with the seats leaking coolant.  To be sure, the test could be repeated with each exhaust valve held open (i.e., rotate crankshaft through the firing order).

 

Lastly, over time I have seen a coolant leak (with EG antifreeze) stain the spark plug insulator.  Have you seen any odd coloring on any of the plugs?  It would likely take a substantial leak over prolonged period, however, so coolant loss in that case would be obvious...

 

 

Edited May 28 by EmTee (see edit history)

[gungeey]

Here one that's showing the beginnings of a failure 55k after install.

I wouldn't call it a full fledged "leak" Some steam is starting to get through resulting in the corrosion seen here. 

(Also notice the bronze liners for the valve guides. 55k. And they say it can't be done....)

What comes out when you stick your fingers in the tailpipe? You can even chant "Bend over, Red Rover" while doing the exam  😂 

 

[NTX5467]

As to that Mr. Gasket type "carburetor insulator gasket stack" . . . DO NOT USE THEM!!!  

 

Reason?  I used them years ago on a Carter AVS on a '70 car I had and that was the OEM carburetor.  Trying to chase a hot re-start issue.  The noted gasket stack looked to be better than the stock thick insulator gasket.  When I put it on, knowing that the gaskets would be "soft and compressible", I was going slowly, in torque sequence, not too tight (the goal), but on one of the torque sequences, I heard a faint "crack" and found a crack in the baseplate beside the ported vac advance port.  Didn't seem to affect anything, but it was still there.  So I bought a new carb to replace the OEM one.  LAST TIME I EVEN CONSIDERED anything like that, especially "the stack".  I started to use the OEM thick base gasket with the steel or plastic bushings in the  carb stud holes.

 

I discovered that the OEM Chevy Truck Holley 4-hole insulator gasket works well with the dual-flange pattern aluminum manifolds.  Edelbrock and others claim you need their adapter, but that GM gasket is well good enough to hit and seal all of the places that need to be sealed.

 

Never have smelt a "vile smell" out the exhaust pipes.  Hydrocarbons, oil, and coolant, but not "vile". 

 

NTX5467

[XframeFX]

19 hours ago, EmTee said:

Have you pressure-tested the cooling system recently?  If the cooling system holds pressure for say, an hour, then you can be pretty sure you don't have an issue with the seats leaking coolant.  To be sure, the test could be repeated with each exhaust valve held open (i.e., rotate crankshaft through the firing order).

Thanks All. This has been going on for so long and I still can't put my finger on what I was hoping to be a root cause. Also, identifying that pungent odor should be a clue. Everyone notices the stink. But experts at numerous car meets are at a loss. "Old Fuel?"

 

After borescoping the combustion chambers 4 years back, I put it out of mind. I did not dismiss the potential of it being a problem but moved on in my trouble shooting and kind of forget about it. Even when I noticed excess condensation out the tailpipes, those inserts did not come to mind.

The failure of exhaust seat inserts was during machining, so I thought. Now I'm hearing they'll eventually leak. This was not my understanding before. If machining and installation was successful, there should be no issue, ever. This especially with my borescope inspection.

 

That condensation appears to be pure water. There is no coolant loss and there's a "psst" when cracking the radiator cap after shutdown. But, I hardly drive the beast. I have it idling more than driving. It drives OK if the wheels are kept rolling. While waiting at a Red Light, that resonance and odor starts wafting into the passenger compartment.

I pressure tested when changing the heater core last summer.

Antifreeze smells sweet. But, would that still be the case when vapourized with hot exhaust gas and then condensed back to liquid at the other end of the Riviera in the cooler muffler/tailpipes?

 

Another thing to consider, I can't pick out any one cylinder lagging behind the rest. What are the chances of all 8 inserts leaking to the same degree?

 

 

Thanks for that image of a clean combustion chamber. Finally a representation of a failure mode after being in-service, not "don't do it, you'll ruin your heads".

Still, if a pair of heads with inserts are reduced to scrap, it would be beneficial to pull out those inserts  to pin-point exactly where jacket water comes closest to the valve seat.

 

55K, that's a lot of miles, meaning start/stop cycles. My valve job is 31 years old with maybe 500 miles since.

The leak is where I have the arrow? My borescope inspection can't identify such detail with the innards coated in carbon and valves in-place.

 

 

Cylinder #2:

 

Edited May 29 by XframeFX (see edit history)

[EmTee]

 

3 hours ago, XframeFX said:

That condensation appears to be pure water. There is no coolant loss and there's a "psst" when cracking the radiator cap after shutdown.

That seems to debunk a coolant leak past the valve seats.  I think the water is condensation.

 

3 hours ago, XframeFX said:

I have it idling more than driving.

 This ^^^ probably exacerbates the issue, as the exhaust system rarely gets hot enough to boil-out all of the accumulated water.

 

Back on the other topic, do you already have a Quadrajet and the associated pieces to install on your new manifold?  I am curious to hear your side-by-side performance comparison...

[NTX5467]

 . . . IF the installed valve seats might "leak"/"seep" under vacuum, might they also do similar under pressure?  Which would suggest enlarged hoses due to too much pressure in the cooling system?  AND would be putting combustion gasses into the coolant, which can be tested for?

 

My suggestion?  Get the car OUT and DRIVE IT more than just around the block or to a local show.  Get it out ON THE ROAD for at least an hour at a time.  Run the gas out of it and put new in, several times!  School's out for the summer!  Time to be driving and enjoying the cars rather than always finding new things to work on them for!

 

Cars, like HUMANS, need to move a lot for best health!

 

NTX5467

[XframeFX]

Thanks for the encouragement Willis!

 

As for "Leak/Seep", pressure/vacuum, it's all no-mans land to me. What triggered removal of the heads above with inserts and bronze valve guides? Prematurely worn guides? Or strange odor?

Too busy now. But, no way am I ever going to "pull the Heads" to test. If I remove the heads, it will be the pair to leap-frog with fresh heads ready to bolt on.

 

Very annoying no one warned me of exhaust seat inserts back in the early 90's when I had it done. I did question the FELPRO Gasket set at the time. Replacing steel shim head gaskets with composite items and Composite intake gaskets with steel shim items, huh?

 

 

Edited June 1 by XframeFX (see edit history)

[NTX5467]

The steel shim intake manifold gaskets work fine.  Chrysler started to use them back in 1958 on their then-new big block V-8s.  There ARE a few things though.  In 1969, with the factory 3x2bbl aluminum Edelbrock intake on the 440 6bbl motors, they ADDED two thin pieces of paper gasket on each side of that metal shim valley pan gasket to keep the aluminum gasket area from being eroded by the harder steel shim gasket, with hot and cold cycles and different expansion rates.  FelPro makes a gasket part number with that addition.

 

On a '67 383 4bbl car which I upgraded to an aluminum Edelbrock intake, I kind of suspicioned (from the way the idle mixture acted) that some sort of minor leak might exist, although none of the normal methods of checking for such indicated a vac seep.  So I got the paper gasket kit with a new valley pan gasket.  I THEN added my "coating with high-heat silicone sealer tricks" to the valley pan.  I put the sealer into the beads of the steel shim gasket and might have also coated the paper items too.  End result is that when the manifold is torqued down, in torque sequence, the sealer compresses against the heads and forms a better seal.  Enough so that I could hear a slight difference in sharpness of throttle response off-idle.  I was pleased.

 

By the later 1970s, Chevrolet had discontinued their .018" (compressed thickness) factory head gaskets with .040" composite head gaskets to lower compression a bit for better tolerance of the newer lower octane fuels of the times.  Nobody complained about "power loss" as the OEM compression ratio was already 9.0CR on the factory performance motors.  Might have later edged up to .060"?  They were also better for people who did not always change their antifreeze each year.

 

FelPro came out with some GREAT new composite head gaskets, back then.  One in particular had stainless steel "fire rings" with a compressible copper wire inside of them.  Basically did the same thing as grooving the block for copper o-rings rather than using the steel shim gaskets, for a better and longer-term seal.  That was more important than the loss of compression on a 10.0CR motor to may racers.  It was during that timeframe that FelPro became a leader in gasket technology and products, much better than any OEM or OEM-style replacement head gaskets.  Which also obsoleted all other gasket makers in the process, unless they chose to compete with FelPro.  Other than Chevrolet, they were the first company to offer "blue" Teflon-coated gaskets for use with factory aluminum heads, as I recall.  They do have several levels of gaskets, IIRC, of which I always leaned toward their more-premium choices for an "at least OEM level" option.

 

When FelPro valve cover gaskets started ot appear at the local auto supplies in the later 1960s, I did not like them compared to the stock rubberized cork vc gaskets.  So I considered FelPro to not be OEM-level, although their type of vc gaskets might have been better in the long run.  Things changed big time by the late 1970s, as they leap-frogged the other brands in features and quality.

 

Just my observations and experieces

NTX5467

[XframeFX]

On 5/29/2024 at 4:41 AM, EmTee said:

do you already have a Quadrajet and the associated pieces to install on your new manifold?  I am curious to hear your side-by-side performance comparison...

I blame unsuccessful trouble-shooting (although some small gains) for making too many changes at once, wanting to fast track and finally do that TH400 swap among others. It is the reason I'm continuing with the original 625 CFM AFB. I have resorted to "one change at one time".

I don't think the aluminum intake is going to affect my Nailhead's crude behaviour. I wanted that spreadbore flange for flexible carburetor selection. I have yet to source a Rochester 4MV, any 4MV. There are still plenty at the wreckers. 

 

I will post any observed change in overall performance but I think that intake should be matched with a 750 CFM carburetor to realize detectable improvement.

 

18 hours ago, NTX5467 said:

Chevrolet had discontinued their .018" (compressed thickness) factory head gaskets with .040" composite head gaskets to lower compression a bit for better tolerance of the newer lower octane fuels of the times.

I now realize my efforts changing the timing chain last year should've been spent on acquiring fresh unmolested cylinder heads instead. On this note, which head gaskets to go with the next time around? With re-surfaced heads, Best composite gasket? Steel Shim head gaskets from T/A Performance, or FELPRO again? I'll examine the latter upon disassembly.

 

Also, any Nailhead cylinder head tips and shortcuts (to keep costs down). Hot tanking, re-surfacing really beneficial? 16 new valve guides for sure and change only out of spec valves, grind/lap the rest. Also, plug that hole at the rear to keep oil off the head gasket. Anything else?

[NTX5467]

As you might know, there are several ways to accomplish "head re-surfacing".  The most common is with what I term "a rotating rock", where the rough-surface rotating rock is spun by a big motor, with the rock being just above the metal surface on which the head's head gasket surface is slid across it.  Allegedly taking off a certain amount of metal with each pass.  Quick and easy, but to me, a bit imprecise as to actual metal removal for each pass.  I never knew what the amount removed actually was, just that you did it until it came out with all new metal on the gasket surface.

 

ONE big issue with the rotating rock is the "speed of the sweep".  If done quickly, it can work as desired.  If done slowly, inconsistent metal removal can happen and ruin a good casting, by observation.

 

The  better choice would be a "rotating cutter mill" (has some formal name) with a large wheel with individual cutter blades/bits on it.  Head has to be leveled on the stands in the machine as the gasket surface is facing upward.  Set-up is key!  Once set-up, the machine is started and the cutter wheel starts it move across the gasket surface.  Each cut can be carefully measured on the dials and gauges.  By its nature, much more precise than the rotating rock!  Also, "angle cuts" can be done, too.  Cutting bits must be dressed often, too, just like the bits on a boring bar.

 

"Hot tanking" of the heads?  Certainly.  Get the accumulation out of the coolant passages for best heat transfer from the head to the coolant for removal.  Seems that rather than the tank of caustic fluid (agitated by a stream of air bubbles), most shops have now moved to a "washing machine" sort of cleaner apparatus.

 

Don't forget about magnafluxing and/or Zyglow checking for cracks after the tanking cleaning activities.

 

Valve guides?  I like the bronze heli-coil style guide modification.  Allegedly, the bronze surface is an excellent interface for chrome-stemmed valves.  Plus, to me, the "endless rebuild ability" of just replacing the bronze heli-coil inserts, it seems.  Guides are done, then the valve seat reconditioning.

 

Over the years, I remember seeing some valves which had a noticeable "lip" on the edge of the valve head adjacent to the edge of the valve head.  I saw this and suspected it was to induce additional turbulence into the incoming air flow for a better total mixture quality.  In watching videos by David Vizard and similar, I now realize those lips were a significant hindrance to max air flow past the valve head into the combustion chamber.  They should be removed or new valves without them used.

 

In buying cyl head cores for rebuilding, knowing what "sunken valves" (due to too many valve jobs) looks like can be important.

 

In the earlier days of unleaded fuels, the best way to deal with an "unleaded future" was to have the competent machine shop install "hard seats" in the heads.  For best long-term results, OEMs were installing them rather than "induction hardening" the normal cast iron seats.  Aluminum heads had them as a normal situation.  So the recommendations became to get hard seats installed at the next valve j0b (about an extra $200.00 USD at that time).  EXCEPT for Buicks!!

 

There were two reasons for not getting hard seats in Buick V-8 cyl heads.  One was the real possibility of "hitting water" as the "valve to coolant" dimension was less than what other brands had.  The other was the harder cast iron mix Buick used was tough enough to prevent valve seat recession from the use of unleaded fuels, it seemed.  Used all the way into the earlier 1970s, at least.  Your decision on this.

 

Just some thoughts and observations.  Personally, anything that FelPro builds is far superior to what the OEMs used for head gaskets back then.  If a bit of compression ratio might be lost, that makes things better as to fuel tolerance, which might allow for a few degrees more initial ignition timing as a result.  That minor loss can also be compensated for with a slight bit more metal removal when surfacing the cyl heads, as long as the chamber cc volume is not less than "blueprint specs".

 

Enjoy!

NTX5467

[RivNut]

8 hours ago, XframeFX said:

I have resorted to "one change at one time".

 

Back to middle school science.  “In any experiment, only change one variable at a time.”  🧐

[carbking]

9 hours ago, RivNut said:

Back to middle school science.  “In any experiment, only change one variable at a time.”  🧐

But if you DO change more than 1 item, and something goes wrong, it is ALWAYS the carburetor, because it sits right up on top where it can be seen!

 

Jon

[XframeFX]

On 6/1/2024 at 5:58 PM, carbking said:

But if you DO change more than 1 item, and something goes wrong, it is ALWAYS the carburetor

It has been awhile before logging actual road miles, not just in-place idling. So, still not adhering to the guideline of one-change-at-one-time between road trips. However, for the 1st time this year, finally got to cruise this week, GOOD!

 

Nagging Nailhead symptoms and current status:

1) Low frequency resonance in passenger compartment while waiting an a Red light in DRIVE - Now GONE 

2) Excessive fuel consumption - Now NORMAL

3) Copious amounts of condensation flowing out of tailpipes - Now DRY

4) Pungent oder, stink! - Now GONE

 

Changes since last test drive (yes, more than one):

1) Dual plane aluminum spreadbore intake purchased from T/A Performance in January.

2) Timing increased 2° for total initial advance of 14°

3) 44K fuel cleaner to 60L of legit ethanol free premium fuel.

4) Replaced bent pushrod for #1 Exhaust.

5) Re-mounted rebuilt Master Cyl. to 1st Gen. Delco-Moriane power booster with plenty of sealant. It still doesn't hold vacuum but gained a couple of inches WC.

 

Note, prior trouble-shooting over the years has always included tweaking of the original rebuilt AFB. This time, the AFB was mounted with an adapter to the new intake with no changes.

 

I did acquire a pair of Core Nailhead cylinder heads with old style rockers as just-in-case backup. But so far, I'm hoping EXHAUST SEAT INSERT WARNINGS BE DAMNED!

 

I opened a 35 year old tin of 44K and as luck would have it, this product IS available in Canada. Opened tin on left and new tin on right in image. Now says: "FOR PROFESSIONAL USE ONLY" Maybe this is why it was so difficult to source, for service shop use only.

 

My 1963 Riviera at a weekly car meet last weekend.

 

 

 

Edited September 12 by XframeFX (see edit history)

[carbking]

Sounds like REAL progress is being accomplished; congratulations!

 

Jon

[jframe]

4 hours ago, XframeFX said:

It has been awhile before logging actual road miles, not just in-place idling. So, still not adhering to the guideline of one-change-at-one-time between road trips. However, for the 1st time this year, finally got to cruise this week, GOOD!

 

Nagging Nailhead symptoms and current status:

1) Low frequency resonance in passenger compartment while waiting an a Red light in DRIVE - Now GONE 

2) Excessive fuel consumption - Now NORMAL

3) Copious amounts of condensation flowing out of tailpipes - Now DRY

4) Pungent oder, stink! - Now GONE

 

Changes since last test drive (yes, more than one):

1) Dual plane aluminum spreadbore intake purchased from T/A Performance in January.

2) Timing increased 2° for total initial advance of 14°

3) 44K fuel cleaner to 60L of legit ethanol free premium fuel.

4) Replaced bent pushrod for #1 Exhaust.

5) Re-mounted rebuilt Master Cyl. to 1st Gen. Delco-Moriane power booster with plenty of sealant. It still doesn't hold vacuum but gained a couple of inches WC.

 

Note, prior trouble-shooting over the years has always included tweaking of the original rebuilt AFB. This time, the AFB was mounted with an adapter to the new intake with no changes.

 

I did acquire a pair of Core Nailhead cylinder heads with old style rockers as just-in-case backup. But so far, I'm hoping EXHAUST SEAT INSERT WARNINGS BE DAMNED!

 

I opened a 35 year old tin of 44K and as luck would have it, this product IS available in Canada. Opened tin on left and new tin on right in image. Now says: "FOR PROFESSIONAL USE ONLY" Maybe this is why it was so difficult to source, for service shop use only.

 

My 1963 Riviera at a weekly car meet last weekend.

 

 

 

I'm assuming that intake fits ok under the stock hood; was thinking of getting one for mine, but I've been hoping to see some performance benefits other than a weight reduction on one.

[XframeFX]

21 hours ago, jframe said:

I've been hoping to see some performance benefits other than a weight reduction on one.

I labelled my Nailhead a "PIG" as it was about as unrefined an engine could be. So, anything aluminum and elimination of as many "PIG Symptoms" is bonus!

"No" to noticable performance benefits although fuel consumption is much better. My Nailhead is coupled to a Dynaslow.

 

Difficult to determine a silver-bullit or a combination of all 5 changes. Symptoms could return!

 

Funny about that pushrod. I delved into more than just a timing chain change. With #1 Exh Lifter clattering more than others on startup and anticipating a bad camshaft, I cleaned out all Lifters and scrutinized that clattering #1 Exh. Finding the valve train good, I replaced nothing. All 16 Lifter pre-loads were good. However, on startup, I noticed previously undetectable bent #1 Exh pushrod turning. No mistaking it was bent! 

 

Myth #1, replacement Lifters will "eat up camshaft lobes". Well, replacement Lifters and my old camshaft appear to be happy, all rotating!

Myth #2, Exhaust Seat Inserts bad on a Nailhead. Hmmm?

Myth #3, Buick castings have high nickel content. Hmmm?

 

[NTX5467]

I'm glad all is working well!  Car looks good, siting there being scrutinized.

 

As BG normally sells to service shops and dealerships only, that could be where the "For Professional Use Only" comes in.  But when vehicle sellers claim something was "professionally done", that just means that they got a sales receipt for work done, no more, no less.

 

Enjoy!

NTX5467