Got a '94 GMC k-1500 Suburban with the weak low compression 350. Been wanting to advance the timing a bit but cannot get the distributor bolt loose, tried special Chevy dist. wrenches, none worked, tried crow's foot just slips off. Lots of Aero Kroil and pounding on it with a drift pin. Anybody else have this problem and a way to solve it?
Distributor hold down bolt
- Thread starter LVJJJ
- Start date
littleblazer
Member
- Jul 6, 2014
- 9,265
Worse comes to worse you could pull the whole intake and get it out from outside the truck. I think it will clear but I don't remember how it was on ours. Hit it with a torch and get it hot then hit it with cold. If the nut is rounded a really good set of vise grips and a cheater pole will probably get it.
If the regular distributor wrench is the one that has a quarter or 3/8 drive coupling both sides together you could also stick a breaker bar on that with the appropriate 12 point socket and that should break it free as well if the head is in good shape. In other words instead of using the other wrench as the lever use a nice long bar.
If the regular distributor wrench is the one that has a quarter or 3/8 drive coupling both sides together you could also stick a breaker bar on that with the appropriate 12 point socket and that should break it free as well if the head is in good shape. In other words instead of using the other wrench as the lever use a nice long bar.
Mooseman
Moderator
Maybe a twist type bolt remover with a breaker bar could work. And as suggested, heat could help.
... and if putting “The Heat” does not work to coax the fitting loose… You might try going to the other end of the Kelvin Scale with “Super Cold” to ‘Chill-Shock’ the Bolt loose from the Engine Block:
https://www.amazon.com/s/?ie=UTF8&k...qmt=e&hvbmt=be&hvdev=c&ref=pd_sl_7oa2onbtig_e
CRC's "Freeze Off" Product Video:
...and a Demo of how the stuff works in the Real World:
Surrounding the area with absorbent Shop Towels will prevent the extra over spray from getting all over the Firewall and down around behind the Bell Housing. :>)
FWIW... Making adjustments out of the factory recommended range of "0" Degrees of Advance (at least on the '99 GM 350 CID Engine) may invite more trouble than it is worth. This "matter of degrees" is covered on a similar but later model K-1500 at this GMT Nation link:
https://gmtnation.com/forums/threads/1999-k1500-suburban-vortec-5-7-problems.16523/
https://www.amazon.com/s/?ie=UTF8&k...qmt=e&hvbmt=be&hvdev=c&ref=pd_sl_7oa2onbtig_e
CRC's "Freeze Off" Product Video:
...and a Demo of how the stuff works in the Real World:
Surrounding the area with absorbent Shop Towels will prevent the extra over spray from getting all over the Firewall and down around behind the Bell Housing. :>)
FWIW... Making adjustments out of the factory recommended range of "0" Degrees of Advance (at least on the '99 GM 350 CID Engine) may invite more trouble than it is worth. This "matter of degrees" is covered on a similar but later model K-1500 at this GMT Nation link:
https://gmtnation.com/forums/threads/1999-k1500-suburban-vortec-5-7-problems.16523/
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thanks for the info, that cold penetrant sounds good, think I'll try it.
As for advancing timing, I already have an MSD Adjustable timing control on it that advances it 15 degrees, I wanted a little more since that 15 degrees is really noticeable. When I driving along with it set at 0, you can feel it speed up as I advance the timing.
Think that cold stuff would work on broken off exhaust manifold bolts? Keep the easyoff from breaking maybe?
As for advancing timing, I already have an MSD Adjustable timing control on it that advances it 15 degrees, I wanted a little more since that 15 degrees is really noticeable. When I driving along with it set at 0, you can feel it speed up as I advance the timing.
Think that cold stuff would work on broken off exhaust manifold bolts? Keep the easyoff from breaking maybe?
The CRC Freezeoff worked so well on the rusted and impacted exhaust manifold tri-studs and gnarled up 15MM fastener nuts on my 1993 Chevrolet Camaro Z28... that after a ten second period of concentrated spray on each one... with just a slight counter clockwise twist... I was able to spin each one off ...with just my fingers... so yes... the stuff really is that good.
The critical thing is to keep the flow of the cooling lubricant going constantly onto the fastener long enough to freeze down the component... and when the tiny spaces open up along the rusted thread-lines... that lubricant really flows inside between the male stud threads and the female internal nut thread-lines.
It is very important to turn your wrench or socket very slowly and not rush the procedure; should you need to re-apply the stuff for a second go at the problem. Wear eye protection if your head and eyes are close to the fittings overhead, as the wasted spray application will pour down onto you during the need for having such an extended spray time.
But in a worst case scenario... with the exhaust manifold completely removed from the Aluminum Engine Head (NOT to be done when attached to the motor for broken stud removal from the head)... This Torch and WAX Technique will work best. The principle is that the Wax will always migrate towards the direction where the heat is being applied:
https://duckduckgo.com/?q=youtube+r...tb=v87-1&ia=videos&iax=videos&iai=cTRUXRv2HFs
But if it gets to this stage .... consider replacing the Exhaust Manifold with a Brand New Dorman version and use the 30 MM Extra Long Cylinder to Flange Bolts at the Head-to-Gasket portion and using the included Brand New Set of Studs for around $100.00 would be much less aggravation. Here are my Photobucket images and data on the Exhaust Manifold replacement gear measured against the OEM EM showing WHY the longer fasteners are needed:
http://s557.photobucket.com/user/60...INEREPAIR/DORMANEXHAUSTMANIFOLD?sort=3&page=1
The critical thing is to keep the flow of the cooling lubricant going constantly onto the fastener long enough to freeze down the component... and when the tiny spaces open up along the rusted thread-lines... that lubricant really flows inside between the male stud threads and the female internal nut thread-lines.
It is very important to turn your wrench or socket very slowly and not rush the procedure; should you need to re-apply the stuff for a second go at the problem. Wear eye protection if your head and eyes are close to the fittings overhead, as the wasted spray application will pour down onto you during the need for having such an extended spray time.
But in a worst case scenario... with the exhaust manifold completely removed from the Aluminum Engine Head (NOT to be done when attached to the motor for broken stud removal from the head)... This Torch and WAX Technique will work best. The principle is that the Wax will always migrate towards the direction where the heat is being applied:
https://duckduckgo.com/?q=youtube+r...tb=v87-1&ia=videos&iax=videos&iai=cTRUXRv2HFs
But if it gets to this stage .... consider replacing the Exhaust Manifold with a Brand New Dorman version and use the 30 MM Extra Long Cylinder to Flange Bolts at the Head-to-Gasket portion and using the included Brand New Set of Studs for around $100.00 would be much less aggravation. Here are my Photobucket images and data on the Exhaust Manifold replacement gear measured against the OEM EM showing WHY the longer fasteners are needed:
http://s557.photobucket.com/user/60...INEREPAIR/DORMANEXHAUSTMANIFOLD?sort=3&page=1
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I've found that because the head of the bolt is on the top of the hold down bracket (duh), that it's hard to get penetrating oil down to the threads. I use Aero Kroil but it hasn't worked yet, but I think its cause I can't get under that bracket. I would assume that the cold will travel down the bolt from the top? The only wrench I've been able to get in there is a crow's foot. Because I bought a cheap set I've actually sort of ruined the foot itself, so gotta get a good set. Appreciate all the help and advice.
Before going any further with the Crow's Foot Tool idea... please try to find this "Proper Tool for The Proper Job" ...as it represents about 99% of your difficulties right now (and if not eBay... perhaps another vendor has one available). Otherwise... you may run the risk of either damaging the Grade 8 Hold Down Bolt or perhaps even snapping it completely off in the block and making a bad situation into one that is well nigh impossible to repair:
https://www.ebay.com/sch/items/?_nk...12&_fpos=&_fspt=1&_sadis=&LH_CAds=&rmvSB=true
About the Thermal Issues Question...The Short Answer is:
Just spray something that gets REALLY COLD as it Evaporates as CLOSE AS POSSIBLE to The Bolt, The Distributor Hold Down Clamp and The Engine Block... BUT DO NOT STRIKE IT WITH A HAMMER AND BRASS DRIFT PIN ...OR IT MAY SHATTER THE ENGINE BLOCK BACK THERE.
This is more detailed answer that will be a bit technical:
The best way I can think of to explain this process... is that as long as you douse the entire area nearest to the interface between the Top of the Engine Block where the Distributor, the Bolt and the Distributor Hold Down Clamp reside... the process should work very well; even if the method you decide to use just involves spraying down the entire area back there with nothing more than "Canned Air" (which is usually just the liquid Refrigerant R-134A) that is used for blowing dust off of computer components and keyboards.
Avoid getting the liquid or spray in your eyes or on your hands as these human tissues will instantly freeze solid and become permanently destroyed... Gloves and Eye Protection are a must when doing this the can of "Canned Air" may actually freeze to your bare, moist hand if you hold down the spray button for a long enough time frame.
For starters... you have the Basic Laws of Thermodynamics on your side in that Heat will always move from wherever is IS... to wherever it IS NOT in any closed system. So the Ambient Heat stored inside of the metals that make up the Cast Iron Engine Block and the Tougher, Harder Steel of the Hold Down Bolt represent a system that while just sitting there in the truck ... have a certain amount of homogeneous ambient heat stored at ‘room temperature’ within them.
BUT... as soon as anything like a blast of REALLY Cold Air or a Liquefied Gas (Liquid Freon) that is in an evaporative state begins to vaporize in very close proximity to those areas... this process ROBS THE HEAT from within those parts in order to power up and excite the molecules of the unstable liquid solvent into performing a 'Phase Change' from a Liquid into a Gas and causing this evaporation to happen in a very rapid manner. And so the heat that was once INSIDE of the Block and Bolt will rapidly get CARRIED AWAY in the process.
What all of this means is that the RUST BONDING present will get broken apart because the Cast Iron of the Engine Block vs. the Alloy Metal of the Steel Bolt are made of DIFFERENT substances... and so they will suddenly lose their in-dwelling heat at VERY DIFFERENT RATES. The end result is that as they will suddenly cool down and contract while their internal heat is literally being hauled away as the solvent(s) evaporate... thus, they will tend to Shrink Down and Break Up Any Rust Bonds that were previously gluing all those components together. When this happens in the presence of the purified lubricant used by CRC in the Freeze-Off... it will rapidly flow inside the freshly broken and rusted up crevices of the Bolt to Engine Block Thread-lines, making the action of Backing out the Bolt so much easier.
https://www.ebay.com/sch/items/?_nk...12&_fpos=&_fspt=1&_sadis=&LH_CAds=&rmvSB=true
About the Thermal Issues Question...The Short Answer is:
Just spray something that gets REALLY COLD as it Evaporates as CLOSE AS POSSIBLE to The Bolt, The Distributor Hold Down Clamp and The Engine Block... BUT DO NOT STRIKE IT WITH A HAMMER AND BRASS DRIFT PIN ...OR IT MAY SHATTER THE ENGINE BLOCK BACK THERE.
This is more detailed answer that will be a bit technical:
The best way I can think of to explain this process... is that as long as you douse the entire area nearest to the interface between the Top of the Engine Block where the Distributor, the Bolt and the Distributor Hold Down Clamp reside... the process should work very well; even if the method you decide to use just involves spraying down the entire area back there with nothing more than "Canned Air" (which is usually just the liquid Refrigerant R-134A) that is used for blowing dust off of computer components and keyboards.
Avoid getting the liquid or spray in your eyes or on your hands as these human tissues will instantly freeze solid and become permanently destroyed... Gloves and Eye Protection are a must when doing this the can of "Canned Air" may actually freeze to your bare, moist hand if you hold down the spray button for a long enough time frame.
For starters... you have the Basic Laws of Thermodynamics on your side in that Heat will always move from wherever is IS... to wherever it IS NOT in any closed system. So the Ambient Heat stored inside of the metals that make up the Cast Iron Engine Block and the Tougher, Harder Steel of the Hold Down Bolt represent a system that while just sitting there in the truck ... have a certain amount of homogeneous ambient heat stored at ‘room temperature’ within them.
BUT... as soon as anything like a blast of REALLY Cold Air or a Liquefied Gas (Liquid Freon) that is in an evaporative state begins to vaporize in very close proximity to those areas... this process ROBS THE HEAT from within those parts in order to power up and excite the molecules of the unstable liquid solvent into performing a 'Phase Change' from a Liquid into a Gas and causing this evaporation to happen in a very rapid manner. And so the heat that was once INSIDE of the Block and Bolt will rapidly get CARRIED AWAY in the process.
What all of this means is that the RUST BONDING present will get broken apart because the Cast Iron of the Engine Block vs. the Alloy Metal of the Steel Bolt are made of DIFFERENT substances... and so they will suddenly lose their in-dwelling heat at VERY DIFFERENT RATES. The end result is that as they will suddenly cool down and contract while their internal heat is literally being hauled away as the solvent(s) evaporate... thus, they will tend to Shrink Down and Break Up Any Rust Bonds that were previously gluing all those components together. When this happens in the presence of the purified lubricant used by CRC in the Freeze-Off... it will rapidly flow inside the freshly broken and rusted up crevices of the Bolt to Engine Block Thread-lines, making the action of Backing out the Bolt so much easier.
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MRRSM, I have tried a couple of those special tools, but haven't found one that will work. It is really tight under the distributor and most tools just hit something. the crow's foot works cause the socket extension goes straight down and the crow's good ducks under just right. Got to buy a good one.