Oil Dipstick Tube Broken in Block, 1972 350

[Larry M.]

[Edward J.]

Re: Oil Dipstick Tube Broken in Block, 1972 350

Larry, I have has some luck with a self tapping bolt, I believe its a 5/16 size, just run it in about half way and use a pair if vise grips to grip the bolt and a flat blade screw driver to pry up from underneath, if this does not work remove the oil pan and drive the tube out from the bottom, Keep in mind the small blocks have a inner tube that that is underneath the dip stick tube, so if you go the oil pan removel you'll see the tube you will driving out from the bottom. This may be the only way to remove as it looks as the tube is chewed up some.

[Ralph S.]

Re: Oil Dipstick Tube Broken in Block, 1972 350

scroll below to similar threads

[Mark E.]

Re: Oil Dipstick Tube Broken in Block, 1972 350

The good news is that removing the oil pan on these cars is a straight forward affair. This may be your excuse to detail your starter, pan, inspection cover and optionally replace the rear main seal.

[Mark E.]

Re: Oil Dipstick Tube Broken in Block, 1972 350

scroll below to similar threads

Who knew this was such a popular problem? Yet another reason to just get a big block.

[Charles B.]

Re: Oil Dipstick Tube Broken in Block, 1972 350

You may be able to take a metal coat hanger or similar stiff wire an turn one end 180 degrees just enough to slide down the broken dipstick tube. Insert it deep enough to catch on the end of the dipstick tube. You can wrap the other end of the wire around a short link of a wood or metal pipe to use as leverage or attach the end to a slide hammer and try to remove it or remove enough to grab it with some vice-grip pliers.

[Joe L.]

Re: Oil Dipstick Tube Broken in Block, 1972 350


Larry------


My opinion is that at this point, the tube remnant is so mangled that I probably would not try the usual extraction methods. At this point, I think your best plan is to remove the oil pan and drive the remnant out from below.

By the way, the thing that usually causes these tubes to break off is the "flattening" of the raised collar during installation of the tube. A great way to "flatten" the collar and damage the tube is to use a flat blade screwdriver on the collar to drive the tube into the orifice. Do this and I can almost guarantee the tube is going to break off at some point.

[Joe R.]

Re: Oil Dipstick Tube Broken in Block, 1972 350

Larry,

Don't forget that if the engine is assembled correctly when you take off the pan you will have the lower dipstick tube to contend with. You may be able to drive the lower tube into the upper and remove both. The lower one is smaller and is pressed in from above before the upper is driven in with a special tool.

JR

[Larry M.]

Re: Oil Dipstick Tube Broken in Block, 1972 350

Gents,

Your responses are greatly appreciated.

Ed - I'll try your bolt/vise-grips/screwdriver method.

Ralph - Thanks for the reminder to look at similar threads. I'd prefer not to remove the oil pan, but I may have no choice. I see one of the threads references a lower tube. I assembled this motor, and don't recall seeing a lower tube inside the block. Of course, that was done in 1988. My memory is suspect.

Mark - Heh. Yes, I thought of the touch-up possibilities as well. Trying to turn lemons into lemonade.

Charles - That's a very intriguing idea; I will attempt that, as well.

Joe - Do you (or any of you) know if I can remove the pan without dropping the power steering linkage? Also, this engine has a windage tray attached with some main cap bolts. Will that tray interfere with access to drive out the stub? And lastly, I know that newer small blocks have a one piece oil pan gasket. Is one available for a 1972 block? If I'm going to go through the effort to remove and replace the pan, I want to re-assemble it with an improved product to minimize leaks. Although, one reason I'd really hate to drop the pan is that my 1988 assembly has proven to be extraordinarily leak/seepage free, and I don't know that I'd be lucky enough to achieve that outcome again.

I'm not going to work on the car until next Saturday; there are some playoffs to watch, and moreso, as 'psyched-up' as I was this morning when I started to finish off a small project, once the tube broke, I immediately 'psyched-down'.

[Larry M.]

Re: Oil Dipstick Tube Broken in Block, 1972 350

Joe,

Thanks; In a reply I just posted, I questioned the presence of a lower tube. I don't recall seeing it previously, but you've just confirmed it's there; thanks.

[Joe L.]

Re: Oil Dipstick Tube Broken in Block, 1972 350

Gents,

Your responses are greatly appreciated.

Ed - I'll try your bolt/vise-grips/screwdriver method.

Ralph - Thanks for the reminder to look at similar threads. I'd prefer not to remove the oil pan, but I may have no choice. I see one of the threads references a lower tube. I assembled this motor, and don't recall seeing a lower tube inside the block. Of course, that was done in 1988. My memory is suspect.

Mark - Heh. Yes, I thought of the touch-up possibilities as well. Trying to turn lemons into lemonade.

Charles - That's a very intriguing idea; I will attempt that, as well.

Joe - Do you (or any of you) know if I can remove the pan without dropping the power steering linkage? Also, this engine has a windage tray attached with some main cap bolts. Will that tray interfere with access to drive out the stub? And lastly, I know that newer small blocks have a one piece oil pan gasket. Is one available for a 1972 block? If I'm going to go through the effort to remove and replace the pan, I want to re-assemble it with an improved product to minimize leaks. Although, one reason I'd really hate to drop the pan is that my 1988 assembly has proven to be extraordinarily leak/seepage free, and I don't know that I'd be lucky enough to achieve that outcome again.

I'm not going to work on the car until next Saturday; there are some playoffs to watch, and moreso, as 'psyched-up' as I was this morning when I started to finish off a small project, once the tube broke, I immediately 'psyched-down'.

Larry------

All you need to do is to lower the steering relay rod at the idler arm. That will usually provide sufficient clearance for removal of the pan.

I don't know why your engine has a windage tray installed. In any event, even if you have to remove the tray, it's very simple and easy. There are only nuts retaining the tray to the studs. I'd be interested in seeing a photo of any windage tray you find.

A one piece oil pan gasket is available for your application and I highly recommend it. The Fel-Pro part number (assuming your engine has its original oil pan) is OS-34509T.

Your engine originally had a lower dipstick tube. However, it is possible to assemble a small block and leave the tube out. If that has occurred it can make it MUCH more difficult to drive out the upper tube remnant from below. The tube is still available from GM under GM #3951600. However, if there is one currently installed, you'll probably be able to reuse it. The lower tube is installed from ABOVE, NOT from below. It cannot be installed from below.

[Jim T.]

Re: Oil Dipstick Tube Broken in Block, 1972 350

First thing, I have never experienced your problem. This is just a thought on trying something before removing the oil pan. Just an experiment. If a self taping appropriate size screw is screwed into the tube and then with a screwdriver the edges of the tube are driven towards the screw could/may separate some of the tube from the pressure fit to the block. Would it be enough, I surely do not know in trying them to remove the tube.

[Larry M.]

Re: Oil Dipstick Tube Broken in Block, 1972 350

Joe,

Thanks; good to know there won't be too much involved in removing the pan.

As regards, the tray, the engine is an LT-1; I believe the tray was part of that engine package.

Thx for the Fel-Pro number; I'll use that if I need to go that far.

I'll have to wait and see what turns up re: the lower tube.

[Larry M.]

Re: Oil Dipstick Tube Broken in Block, 1972 350

Jim,

Thanks, yes, that sounds like that would work; but not, I believe in my situation. There's basically no portion of the tube remaining above the surface of the block flange to work with. I think I ruined whatever chance I may have had to work with it externally by my earlier attempts.

[Joe L.]

Re: Oil Dipstick Tube Broken in Block, 1972 350

Joe,

Thanks; good to know there won't be too much involved in removing the pan.

As regards, the tray, the engine is an LT-1; I believe the tray was part of that engine package.

Thx for the Fel-Pro number; I'll use that if I need to go that far.

I'll have to wait and see what turns up re: the lower tube.

Larry------


Yes, the LT-1 may have used a short windage tray of GM #3989075. This windage tray will work with the 5 quart oil pan. I'll be able to confirm if I see a photo of it.