Odd coolant leak

[ozzmonaut]

So I had the generator rebuilt on my 48 Special deluxe. I was reinstalling it and had loosened the water pump bolt that also secures the generator adjustment bracket . When I attempted to tighten the bolt back down, it quickly stripped and coolant started pouring out around the bolt. I have never known any threaded hole to enter into a coolant channel of a block. The bosses ALWAYS are to the sides of the channel. Coolant is not leaking around the pump body. It only pours from the bolt hole. Before I start disassembly, what am I dealing with? My only assumption can be that the boss that stripped also cracked internally, allowing coolant to flow outside of its intended path. Any help is appreciated.

[Dodgeb4ya]

That generator strap mount bolt does go directly into the coolant passage sorry to say.

[Plymouthy Adams]

a large majority of engines have bolts that enter the coolant passages...as for the strip...are you sure it stripped or broke and the rust is such that it will not turn out or tighten ?

[ozzmonaut]

I will not know until I get the pump off. As of now, the bolt does not have room to pull out before hitting the back of the pulley, so it probably just stripped. It was not tight or difficult to turn though. Once everything is apart, I may find that a longer bolt will let me catch some more threads. I would hate to have to tap it to a larger size.

Edited December 20, 2019 by ozzmonaut

[Tom Skinner]

Ozzmonaut,

It will not be to much to have to Tap it out a tad larger with a Tap and a Larger Bolt. You may have to chase a bit through the Water Pump opening also to allow it to go larger.

Also use a Silicone Tape or Dip when re-installing on the threads of the new bolt to prevent coolant leak going forward.

Tom

Edited December 20, 2019 by Tom Skinner
more info

[Bbdakota]

A heli-coil will allow you to use the same diameter bolt.

[Jerry Roberts]

Some of the head bolts and some of the manifold bolts also go into the water jacket . 

[Andydodge]

Make a note of what bolts are from what holes, ideally use a piece of cardboard and insert the bolts into it in the same layout as the water pump has........when its removed, check each threaded hole for striped threads, also measure the bolts and check whether they actually have enough thread to go thru the water pump and sufficently into the block........the danger of screwing bolts into the block is one reason why studs are sometimes used and all there is is a nut which holds the item, water pump in this case on......however the problem with studs is that they can corrode or rust into the item being held and make its removal very difficult..........either way any bolt or stud screwing into a water jacket or likely to should have a sealer of some sort used liberally on the threads to make sure water doesn't wick along them..........BTW.........Welcome Aboard from Oz.............andyd    

[DonaldSmith]

I wound up installing a stud instead of a bolt, as the fastener in question.  Thread sealer on the stud.  

Then a lock washer and nut to secure the water pump.

Then the arm that secures the top of the generator (or alternator).

Then a nut, installed loosely, to allow the arm to pivot when tightening the fan belt.  . 

Then a cotter pin through a hole drilled in the stud, to keep the loose nut from backing off. 

This allows adjusting the fan belt without disturbing the water pump fastener.    

[Plymouthy Adams]

12 hours ago, ozzmonaut said:

I will not know until I get the pump off. As of now, the bolt does not have room to pull out before hitting the back of the pulley, so it probably just stripped. It was not tight or difficult to turn though. Once everything is apart, I may find that a longer bolt will let me catch some more threads. I would hate to have to tap it to a larger size.

 

pulley the fan and pulley.....if bolt comes out without threads...broken...if comes out with rounded threads or threads with cast iron embedded in the grooves....you got mechanical issues which if rounded may be chased with a tap and cleaned up and new bolt installed...if embedded, you would first address this with a helicoil install.  Either way, rear the crime scene so to make the right call

[Dodgeb4ya]

5 hours ago, DonaldSmith said:

I wound up installing a stud instead of a bolt, as the fastener in question.  Thread sealer on the stud.  

Then a lock washer and nut to secure the water pump.

Then the arm that secures the top of the generator (or alternator).

Then a nut, installed loosely, to allow the arm to pivot when tightening the fan belt.  . 

Then a cotter pin through a hole drilled in the stud, to keep the loose nut from backing off. 

This allows adjusting the fan belt without disturbing the water pump fastener.    

When the pump fails you will have to pull the radiator if you use studs.

Way too much hard work that's not really necessary.

1/4 turn loose on the pivot bolt is plenty to let the generator pivot.

The generator pivot bolt threads if they do start to leak coolant usually stop leaking when the pivot bolt is tightened firmly.

I don't loosen the pivot bolt if I don"t need to.

JMO. 

 

[Loren]

Another 2 cents.

When you replace a bolt (or stud) that goes into a water jacket make sure it is only long enough to use all the threads in the block plus no more than one.

If a bolt is too long it will corrode inside the water jacket and will be a candidate for breakage at sometime in the future when removed.

Also use plenty of thread sealer such as Loctite or ARP's Stud sealer. They will stop corrosion on the threads and counter intuitively make it easier to remove later on.

All threaded holes should have a tap run down them and cleaned out with a blast of air or carb cleaner.

BJ Blaster or Kroil is a God send on threaded fasteners.

On blind holes when a bolt or stud breaks use a "Left handed" drill bit in reverse to get the stub out. If you're lucky it will catch and unscrew the stub.

For thru bolts use a regular drill bit in forward to screw the stub into the water jacket (because it isn't coming out).

Next tip is to get a "Drill Bushing" and a drill which just clears the threads. You might have to have the outer diameter (of the bushing) ground down to fit the associated part (in this case the water pump) or carefully drill out the hole in a scrap part to the size of the drill bushing (on a mill or Drill press you've checked for straight).

For an explanation of this go to www.syndersantiqueauto.com,  Model A,  Engine,  Motor Parts, (bottom of the page) Head Stud Drill Out Kit,  View Details.

Basically you use the cylinder head to hold the drill bushing straight and in the right place. I've done 6 Model A head studs and they all turned out like new!

You will spend sometime picking the remains of the stud threads out and you'll benefit if you have air pressure but you won't regret the effort. 

HeliCoils are an unsatisfactory solution for a last resort fix.

[Plymouthy Adams]

I disagree with your heli-coil remark....but will agree if you are not accustomed to doing insert jobs...you may wish to try something else.

[Sniper]

A spent plenty of time putting helicoils in aluminum castings when I was in the service.  Done right they are better than the original threads, even in cast iron.  Not too sure how water tight they might be though.  A timesert is an option though you will need to buy tools to install it properly.  If you find the hole is too big for the right size helicoil or a timesert then you should consider a keensert.  A link for you to consider https://dsportmag.com/the-tech/three-ways-to-fix-damaged-threads/

[Loren]

1 hour ago, Plymouthy Adams said:

I disagree with your heli-coil remark....but will agree if you are not accustomed to doing insert jobs...you may wish to try something else.

 

28 minutes ago, Sniper said:

A spent plenty of time putting helicoils in aluminum castings when I was in the service.  Done right they are better than the original threads, even in cast iron.  Not too sure how water tight they might be though.  A timesert is an option though you will need to buy tools to install it properly.  If you find the hole is too big for the right size helicoil or a timesert then you should consider a keensert.  A link for you to consider https://dsportmag.com/the-tech/three-ways-to-fix-damaged-threads/

 

It's a matter of opinion of course.

An original thread is straight and well made even if it's a little worn.

Helicoils are usually slap-dashed repairs made by uncaring shade tree mechanics, from my experience.

I spent too many years working in dealer's service dept.s and I wasn't impressed by my co-workers.

When you have to follow somebody else's Flat Rate repair you don't have a high regard for things like Helicoils and Scotch-locks.

Timeserts and Keenserts are much better if done well...if not then the scrap pile grows.

And yes I have used Helicoils (and keep a set of 8mm x .125 and 5/16 x 18 close at hand) but only when I have no other choice.

 

I have a 25" block with 3 broken manifold studs in it.

Since it is very heavy and a little too big for a Bridgeport mill, I am going to rent a "Magnetic Drill Press" to drill them out.

That way I can be sure to drill straight. I am going to make a fixture for a drill bushing that will be held down with two other stud holes so it won't wander.

In this way I will try to save the original threads. 

[Sniper]

the key take away from my comment is "if done right".  Anything can be crap if done poorly.  there is a reason I do my own work whenever possible, even if I have to teach myself how first.  I find that most aren't as attentive to detail as I am and I seriously hate hack jobs.  My 51 must have had one of those coworkers you mentioned working on it.  I have found many hacks on it and I am fixing them as I find them.  From axle flange nuts finger tight with only the cotter pin keeping it from spinning off, to lower brake pivot bolts with a 1/4" gap between the nut and the backing plate, to a new wiring harness spliced into the old and a pushbutton start cobbled into where the cigar lighter should be.  I'm not advocating replacing usable original threads, but if it's not usable I prefer to use an insert to keep the correct bolt in there rather than going with an oversized one necessitating a further mod to the pump to make it work.

[Tooljunkie]

On 12/20/2019 at 2:23 PM, Plymouthy Adams said:

I disagree with your heli-coil remark....but will agree if you are not accustomed to doing insert jobs...you may wish to try something else.

Heli- coil will likely leak. However, a nut-sert will not. But it woukd taje some effort to make it flush at pump mounting surface. 

[Plymouthy Adams]

again I disagree, there are proper methods for installing the heli-coil that it seems so many here are missing....properly installed you will not even know it is there.  

[Los_Control]

Going with pa on this one, seems like the factory ford mistake was to helicoil the spark plugs on their goof up.

I have helicoiled a spark plug on a toyota for other reasons, and never had a issue with it for years, was other reasons I junked it. (carburetor)

 

helicoils work well if done right, and spark plugs under engine compression is about as good example as you can get.

[kencombs]

Take a look at almost any aircraft piston engine and you'll find a LOT on Helicoils.  Excellent repair.  Drill straight, tap straight, install with the tool, break off the install tab.  Perfect threads that are much stronger than aluminum or original cast iron.

 

Of course the inserts of various types work good also and have specific uses.

[Loren]

I totally agree that Helicoils done right are great.

A lot of new stuff is engineered to have Helicoils especially in aluminum.

We all remember VW case savers. Eventually VW put them in at the factory before the head studs could pull the threads out.

A Helicoil can actually strengthen the fastening by spreading the load over the larger thread (which is the reason VW installed the case savers at the factory).

My beef with Helicoils is the slip shod way some people install them. They don't bother to re-drill the hole after they have butchered it or if they do it isn't round or straight or it's oversized. I've seen the tab wedged in the bottom of the hole, a turn of the Helicoil bent and out of it's groove or the hole too shallow for the Helicoil. A through hole gives most guys a better chance to get it right than a blind hole.

There is just a whole lot that can go wrong. I'd much rather not have a part that's been Helicoiled when I have a choice.

Just my humble opinion, a Helicoil can save your butt or it can make for bad day if you have to follow someone else's mistake.

[Sniper]

Putting in Helicoils isn't brain surgery.  A shop vac takes the broken off tang out of a blind hole pretty easily.

 

Here's a good video of the process, I like how he mentioned turning the tap back a quarter turn to break and chips free during the tapping process.  Too many people just chuck up the tap in a drill and have at it.  Not a good ideal as you could break off the tap and then you'll be unhappy.  One thing I do that he doesn't mention is clean to the hole with brake cleaner to get any cutting oil cleaned off before putting in the Helicoil.  In a blind hole I will use the shop vac to suck out any chips while blasting it with the brake cleaner.    Of course you do have to drill and tap the hole squarely but attention to detail should be sufficient especially since you are now aware that is an issue.  If you want to fab up a jig or use a magnetic drill press to ensure it then that's fine too.

 

 

[desoto1939]

Seems as if someone might have replaced the threaded stud at some point in time. On my original 39 Desoto engine I have three threaded studs that come out of the front of the engine block and there are three nuts that hold the entire water pump to the engine block.  The one nut also is used to hold the generator top support meatal bracket.

 

I do know that in the later 40s the main body of the water pumps were changed and the stud that is on the left side when looking from the front of the wp is now replaced with a threaded bolt because they increase the thickness of the body of the new styled WP.   If you have one of the older style pumps the body will only be approx. 1/2 thick at the point that I am referencing.  So if you can not get one of the older pumps then you will need to use a stud puller to remove the stud and then use the supplied bolt that comes with the newer sealed bearing pumps.

 

If you or anyone has any old style pumps I am interested in purchasing these older style water pump bodies.

 

Rich Hartung

desoto1939@aol.com

[T120]

On 12/20/2019 at 2:48 PM, Loren said:

 

 

 

 

I have a 25" block with 3 broken manifold studs in it.

Since it is very heavy and a little too big for a Bridgeport mill, I am going to rent a "Magnetic Drill Press" to drill them out.

That way I can be sure to drill straight. I am going to make a fixture for a drill bushing that will be held down with two other stud holes so it won't wander.

In this way I will try to save the original threads. 

 

I have used a Makita angle drill to successfully drill out studs  in tight places and perhaps while overkill I used cobalt drill bits starting with small diameter,even managing to save  original threads....

 

 

Edited December 22, 2019 by T120