How far should I go with this engine

[Wheelmang]

10 hours ago, keithb7 said:

@cahartley thats a great idea to source a knock. If by chance say #1 had a knock, has there been much success in pulling oil pan and installing new bearings? Just in the problem hole? Or hardly worth it? I suppose other factors should be considered to determine engine health. Oil pressure. Compression. Oil consumption. Etc. 

If/when I drop the pan again, and find a bad bearing, all rod and crank bearings will be replaced. Cannot see the justification in replacing just one or two. Possibly just need different shims? Right now budget and honey do list (Wife's Jag is now occupying the DBs spot in the garage. P0121 code) say wait. Compression seems fine. I am in the process of making an adapter for my compression tester to make sure though. Could not find one anywhere for that size plug hole so am going to use an old spark plug and machine the inside to fit one of my existing adapters.  

[Wheelmang]

My apologies to all of the Vacuum tank purists out there.  I have decided to go with an electric fuel pump and pressure regulator on this. I am not a master mechanic by any stretch but have done all of my own vehicle repairs from brake jobs to engine overhauls and body work for 55 years and have met my match on this tank. I have done everything that has been recommended here as well as in the manuals all to no avail. I just want to go for short rides for now and for the price of the pump - that is what is going to happen. 

Thanks all for your valued assistance on this frustrating venture. 

[MikeC5]

Keep in mind that loose bearing clearance might be fixed by removing a shim or two but a bad main bearing will require block removal and re-babbitting/reaming (unless things changed drastically from '25 to '26 block that is).  Rod bearings don't require pulling the block but you will need accurate crank journal dimensions so the new rods can be reamed for correct clearance.  You can't just swap in new bearing shells but you probably already know this.  At least dropping the pan is pretty easy on these.

Edited March 2, 2018 by MikeC5 (see edit history)

[dwollam]

Didn't see it mentioned anywhere in this thread but there will not be a ring ridge on any of the Dodge Brothers 4 cyl engines. Ever. The top ring comes all the way to the top of the bore, so no ridge is possible. Hence, no ridge to cut but also no ridge to show how worn the cylinder is! Measuring is the only way to tell on these.

 

Don't be afraid to remove rod bearing shims, just use plasti-gauge to check clearances. Be careful doing main bearings, especially the center main(s) Don't want to have the crank bending and flexing because it is no longer aligned. Make sure crank turns easy by hand with rods disconnected when tightening the mains up. You should be ok if it moves freely.

If the engine does not have shims, as they didn't come that way originally, the thick metal "shims" that hold the bearing shells in the rods can be machined down to take up clearance. If you machine too much, then add the thin brass shims to correct clearances.

[Wheelmang]

10 hours ago, dwollam said:

just use plasti-gauge to check clearances.

Great info  - Thanks. It will be a while until I drop the pan but does anyone have a range of acceptable clearance for rods and mains on this?

Thanks

Paul

[Wheelmang]

On 3/5/2018 at 11:20 PM, dwollam said:

just use plasti-gauge to check clearances.

Looks like I will be dropping the pan in the next few weeks. What clearance should I be shooting for?

Thanks

Paul

[Guest]

Without any specific figures a basic clearance is .001" per inch of journal diameter.

[Wheelmang]

I took my wife for our maiden voyage today. Almost a year after bring the DB home from Minnesota. She loved it!  (me too)  Wasn't a long ride, just to a friends house. Foot brake kinda slows it down, emergency will lock them up. Really steep hill on a dirt road to get back to my house but handled it just fine in first gear. 

Vacuum tank fixed. There really wasn't anything wrong with it just the mechanic who reassembled it after cleaning and at least 6 times after that. Just in case anyone else may be ready to give up on their tank, check to make sure the needle on the bottom of the float in the inner tank is centered in the hole in the bottom of the tank. If it is not, it is quite easy to reassemble the tank with the needle not in the hole. The end result is the float is all the way to the top of the tank and it shuts off the fuel supply just like it is supposed to when the tank is full of gas. 

 

Thanks to OLDCARFAN.  Tim insisted on not giving up on the tank. Now I have a brand new, never been used electric fuel pump in stock.

Next project (after finishing the paint job on my wife's car) is a compression test. I made an adapter for my compression gauge out of one the old plugs. Did not see one in the Snap On listings. After that drop the pan and plasti gauge the bearings. At least one is knocking. Oh, and the steering - it has a mind of its own. 

Thanks all for your great guidance in helping to get to this day.

Paul

 

[MikeC5]

Glad to hear that you got the vacuum tank working.  I think you have a Gemmer steering box on yours.  There are things you can do to improve them but also take a look at your king pins and tie rod ends too.

[Spinneyhill]

Steering: my 1930 Dodge Brothers 8 had 3" free play at the steering wheel rim. I had the sector shaft rebushed to very close tolerances and the shaft ground if it needed it. I think I put modern seals in it too. That brought it all back to 3/4" free play. I couldn't get new upper and lower bearings, they are NLA. The old ones were in very good condition, however. Mine is very drivable now. Also, as above, make sure the drag link and tie rod ends are not allowing movement and the king pin bushes and shims are also "tight". Remember to use a semi-fluid grease lubricant in the steering box.