300+ rebuild

[BottleHauler84]

3 hours ago, Joey Mack said:

Freighttrain... I hope you dont mind if I Hijack a page or 2 on this thread?  Im trying to help Bottlehauler.

 

Thank you Joey!

@Freightrain I've been following along. This is a great thread. Thanks for keeping the posts coming!

[Joey Mack]

Are the 443 seals what you need,  BH ?

[Freightrain]

I think I have a plan.

Remove the inner sleeve.and then shorten the length to make it just like the 673.

I think it will work out fine.  The wear spot from the seal will be inside past the seal because shortening the sleeve length will move the seal outward toward the flange.

 

Looks doable.  Luckily I know a guy at a machine shop....😉

[BottleHauler84]

4 hours ago, Joey Mack said:

Freighttrain... I hope you dont mind if I Hijack a page or 2 on this thread?  Im trying to help Bottlehauler.

 

I do believe those are what im after. 

[Joey Mack]

Thanks Freightrain.  We will use P.M. from now on... Jojo

[other dog]

When is the first race? Maybe we should get started on a "go fund me" so you can afford some fuel for the truck and some gas for the race car.

[mowerman]

Great progress … let’s keep it up 

[Freightrain]

Oil cooler rebuilt and hanging on the block.  I won't torque it down until I get the water pump housing installed so I can line up the holes.

Will get water pump cleaned up next and get housing put in block.  

 

The pile of parts is decreasing at a steady rate.  Whew......

[mowerman]

lol Larry, I love that last comment.Nice going  man let’s keep it up. You’re certainly well on your way.

[mowerman]

After all that fist fighting with the injectors, everything else is going to look easy or at least here is hoping

[mowerman]

Be a while for me it’s been snowing on and off past few days won’t be able to move that bucket of bolts for a couple of months not cool

[Vladislav]

On 2/17/2026 at 5:58 AM, Freightrain said:

I think I have a plan.

Remove the inner sleeve.and then shorten the length to make it just like the 673.

I think it will work out fine.  The wear spot from the seal will be inside past the seal because shortening the sleeve length will move the seal outward toward the flange.

 

Looks doable.  Luckily I know a guy at a machine shop....😉

You can do that with a corner grinder  Accompanied by a caliper for control of evenness and a piece of sand paper put on glass for final finishing of the end.

Sure machine shop is much better option!

[Vladislav]

So those valve seals for 0,5" stems - are they Mack part? Which engine were they supposed to be installed onto originally? 

I knew that stuff for E7 Joey posted but never heard of seals for 1/2" stems.

BTW my Lanova engine also had 1/2" stems both intake and exhaust and it used steel caps put under the stem upper dishes for "shielding" the oil. 

[mrsmackpaul]

3 hours ago, mowerman said:

Be a while for me it’s been snowing on and off past few days won’t be able to move that bucket of bolts for a couple of months not cool

Not cool or to cool

I'll be out in my bucket of bolts running hay again tonight 

Rolls of hay go this way, rolls of hay go that way 

Stuff just goes round and round lol

 

Paul

[cruiseliner64]

At least your keeping busy Paul.....

Paul

[Freightrain]

3 hours ago, Vladislav said:

So those valve seals for 0,5" stems - are they Mack part? Which engine were they supposed to be installed onto originally? 

I knew that stuff for E7 Joey posted but never heard of seals for 1/2" stems.

BTW my Lanova engine also had 1/2" stems both intake and exhaust and it used steel caps put under the stem upper dishes for "shielding" the oil. 

My 237 had 1/2" stems, as the lash caps for the Jake's will work perfectly on the 300.

I never had valves out of 237 so don't know if it had seals?  The 300 heads definitely do have seals.

[Freightrain]

I cleaned up the water pump housing and got it bolted on.  The lower water hole was previously rusted out and a helicoil was installed.  It seems ok and torqued down to 55ft/lb ok.

I was concerned about my water pump and wanted to look at putting bearings in it.  It didn't leak but when spun it had a looseness to it and you could hear a faint rumble from old bearings.  The Mack manual shows how to rebuild it but takes a special puller to get vanes off the shaft.  I played around but figured it would be better just to replace it.  I googled and found a 673 version.  The 300 is about 1/2" shorter shaft and no keyway for pulley.  I am going to call on the reman version and have a known good pump.

I'm taking crank hub to shop Sat to press it apart and machine it.  Assemble the heads and get them home so I can get them set on.

I made a list of silicone hoses to replace all the old lines that hook stuff together.  Water manifold, intake, oil cooler, turbo.  $100 at Summit racing.  I did the same for the 237.

Things should really come together this coming week.

 

[Vladislav]

I've taken apart and overhauled/restored two water pumps - for Lanova and for E6-350. Provided all the works with basic shop tools. You take the assembly in halves than take the rotor off the shaft using a suitable puller than pull the shaft with both bearings to the outer side (front of the vehice). Than pull the bearings off the shaft and wash them refresh the grease or just renew them. The seals I dealt with were of different styles. Lanova had a carbon setup and my Dutch friend supplied me with NOS repair set. E6 had unified seal which was avalible from PAI and easy to replace. For some reason I've stocked up with a couple more PAI seals. To me it looked like you could upgrade an old pump to that unified seal applying some ingeunity and lathe work. 

[Freightrain]

Progress today ..

Heads assembled, almost.  I tried checking spring pressure but the outers are too tall for buddies checker without screwing with it and making him reset it for his daily work.  I checked free height and they all were right about the same besides being a bit short of "spec".  The inner spring I could check pressure and even being about .07 short it was within pressure.  So I checked all heights and all but one outer was within same height.  I left it apart and will being getting some spares from Mack buddy.  

I machined the crank hub.  All is well.

Only issue is one small spot where it is marked.  A few pit marks and I am going to get a speedi sleeve for it.  The rest is perfect condition so there is no need to leave a chance for seal to tear on those marks.

I checked and marked my balancer for correct TDC.  I'm using my old 673 and it has no factory marks. It has a timing mark on flywheel.

I did TDC and up to 30* plus 120* each way.  Taped it and used yellow highlighter.  I will paint around them and then clear over timing marks.

Far from perfect but will be nice when needed.  The long stripe is TDC, the shorts are 5* increments.

The keen eyes will see GOLD paint behind the balancer.  I stopped and found another shade of gold and it looks good!  So I will be getting more.

Rust-Oleum metallic champagne gold.

[mechohaulic]

possibly things are different now then back in the "dinosaur days"; speedie sleeves which were installed on front crank hubs didn't come with a deeper install  tool(cup). modifications were needed to install sleeve without damage to it. hose clamp ???

[Joey Mack]

I dont know that the seal will ride where the little dings are.  What say you,  mech ?

[Freightrain]

I have a piece of 3" exhaust tubing to get the sleeve on deep enough.  Been there, done that.  If needed, you then tear off the shoulder of the sleeve.

The black magic marker is where the seal rides.  I used calipers to confirm exactly.  Look at the 673 next to it, the shiny spot is where it rode.

[Joey Mack]

Yep. Sure is.   Good call. 

[Freightrain]

Ok, next question for the day.

How do you get injector seal washers out.  I have 4 out(fell out).  Two are stubborn.  Used a wide screwdriver and tried to tap into copper and twist(read that somewhere) but nothing.

Thoughs?

[Vladislav]

A drill bit to cut its blades into and try to move?