Retorquing procedure

[SteveK]

I’ve been tinkering with my T for a few months now and have the engine running well. A few days ago I noticed a small water leak from the head gasket on the front of the motor to the right of the water outlet. There is no water in my oil and no bubbles in my radiator so I’m pretty sure it’s a gasket to water jacket issue. But before I pull the head and install a new gasket I feel it’s worth trying a retorque first. The head has been together for at least 40+ years so no telling how stuck the bolts are. I’m thinking following the torquing sequence I will back off each bolt 1/4 turn and then retorque to both 50 lbs first cold and then do it over again hot. Of course if any bolts break it’s “off with the head”

Comments would be welcome

Thanks

Steve

[John kuehn]

I would back off all the head bolts at one time then start in the middle and evenly work you way out.
Torque to 50 lbs then till it’s hot and retorque starting from the middle as before. Others will have ideas too.
If you remove the head because it still leaks clean out the bolt holes really well. Lots of bolts have been stripped and bolt holes because the holes weren’t cleaned out to the hole bottom.

[RajoRacer]

I believe 50 lbs. is a bit too much - I'm in the 40-45 lb. camp & I always re-torque after a considerable cool-down !

[John kuehn]

You might also try to clean out the bolt holes with a log screwdriver that will reach to the bottom before you remove the head. Then use air to blow out the scale and debris if any. But do not go over anxious with the torque wrench and go over 45-50. Old head bolts can get stretched too so check that also.

Check the head bolts threads too. Others have worked on your T before you and you may have some questionable bolts! The bolt in the back I don’t think you can get out all the way because it will hit the firewall depression but the rest you can.

[Craig Leach]

Hi Steven,
Had the same thing happen same place retorqueing did not help. Added a 1/3 bottle of K-seal & the leak stopped then had to repeat a few
years later. Then I flushed & cleaned the cooling system & got the leak back, used the last 1/3 bottle & its good again.
Craig.

[jiminbartow]

Folks torque in their own sequence. As long as you spread the sequence in a balanced way across from eachother and staggered, it should be alright. Here is one sequence. Use the same sequence when loosening or tightening. As you remove the bolts, blow the holes out with the head in place so the debris does not get in the cylinders and clean the threads with a wire brush. You may want to dislodge the hard compressed debris in the bottom of the holes with an ice pick, if necessary. Jim Patrick

[Norman Kling]

Torque the head when you first install the gasket. If you are using a steel head, torque again when it is hot. Then drive around a bit and with it still hot, torque again. Do this over and over until it remains at 45 ft lbs.
However, if your head is aluminum, torque when cold then warm up and let it cool down completely and torque again when cold. Do this a few times until it holds it's torque. The reason for this is that aluminum expands at a greater rate than steel, so it will be loosest when cold.

One problem I had on one of my T's was that the last bolt in the back was stripped, so I installed a helicoil. This was many years ago but several times I blew out the rear gasket near the steam vent at the corner behind the manifold. It seeped out slowly and when I would check the coolant and then load on the trailer. Next day I went on a tour and it overheated and blew out the gasket in that corner. Problem was that when I installed the helicoil, the bolt hole was about 1 1/6 inch too shallow. The torque wrench was reading full torque but the head of the bolt was not all the way down. I installed a washer on that bolt which solved the problem.
Norm

[Craig Leach]

I'm working on a friends 26 I like to clean all the threads in the block with a old bottoming tap. ( nut a new one ) the goal is to clean not cut
threads I found in this block that there was no two holes the same depth. Found two hole stripped & had to Helicoil them. One left a 1/4"
under the Helicoil & the other was to shallow to botton the Helicoil & I had to remove 1/2 of a thread to make it flush. I install the new head
bolts without a head gasket to make sure they are not to long then mark them so they dont get mixted up. Some have to be shortened in the
lathe. but make sure you get as much thread as you can. There are torque specs for clean & dry & lubed bolts I prefere the lubed ( it will be
less than dry) but I feel it is more accurate. JMHO. If you choose to use washers to adjust thread depth use good machine washers not
Hardware store washers.
Craig.

[jiminbartow]

If I’m not mistaken, won’t a tap compress the material in the bottom of the hole? I like the idea of using a tap to clean the threads, but shouldn’t you scrape the bottoms of the holes and blow them out prior to tapping? Not doing this might be the reason for the variation in depth. Jim Patrick

[RajoRacer]

You need to use this tool to properly clean out the block threads !

[Craig Leach]

Yes James that's correct. Always clean & blow out the holes first. I stated that I use a old bottoming tap because if you
use a new tap you can cut to much & oversize the thread. The objective is to chase the threads not cut new ones.
7/16 thread chasers are not very common so if you have to use a new tap you might consider taking it to the wire
wheel & knock the sharp edge off of it first so it will only remove crud & not block.
Craig.

[John kuehn]

Several good comments and I’ll add one more.
When using a bottom tap as Rajo says and if you pull the head clean out the block water circulation holes and the head water circulation holes in the head. Carefully use a drill bit with a bit just under 1/4 “ in size. You’ll be surprised after many years the holes get scale in them. If your T hasn’t had the head off for many years you can almost bet it needs it.
If you have air blow out the head and block water jacket holes too. Use some rags and put in the cylinders while you’re doing that.

Your T needs all the cooling it can get and a cleaned out water jacket is one of them!

[RajoRacer]

The photo of the tool I posted is not a bottoming tap - it's made exclusively for cleaning threads - not re-tapping ! Available at an engine machine tooling company.

[SteveK]

Thanks everyone for all of the comments, they are very helpful! Tried to send a reply about an hour ago but I guess it got lost in cyberspace.

I just tried to loosen some bolts; the first 2 had no issues but the next 2 would not budge and i didn’t want to force them. So I torqued the 2 i pulled back to 45 and will go the leak stop route for now. I will order a new copper gasket and new bolts since I’m sure at some point I’ll be pulling the head. A couple more questions however;

What are the specs on the thread clean out tool. I’m in Hawaii and there is no place to carry a bolt in to buy one so I do have to order from the net. I tried to look through the forum and Google but have not found the bolt thread count anywhere?

Anyone have experience (or tricks) on breaking the stuck bolts free without breaking them. On my more modern cars 50’s and 60’s they always came loose with a slight tap of the hammer but they were not 100 years old!

Thanks in advance!

Steve

[DanTreace]

Head bolt sizes.

Caution on using a bottom tap or thread cleaning tap with the cylinder head still in place. As you withdraw the tap, debris can fall free back into the hole when pulling up through the cylinder head holes. The debris may still remain as you have to blow out the residues at the bottom of the block hole.



On really frozen bolts, you can try to pool a very good penetrating oil around the bolt head and cylinder surface after wire brushing to get a bit of gap between the bolt head and cylinder. Then tap on the bolt head to help vibrate crud loose. Many times the rust crud is locking the upper shaft of the bolt inside the head. Or worse case, the threads are locked with rust into the block. Gentle going is a must. Be prepared to Heli-Coil in the event of busted bolt.

[jiminbartow]

You can slightly tighten the stuck bolts which may break them loose so they can be removed. Penetrating oil such as “Blaster” or “Kroil”, applied at the base of the bolt heads several times, may sink in overnight and allow the bolt removal the next day. Jim Patrick

[RajoRacer]

Give 'em a good whack with a hammer - I do that quite often on a stuck bolt.