Topic: Threaded Oil Dipstick Tube in Timing Cover, '69 351W

[drummingrocks]

Ok, I apologize in advance for flooding the '69-70 forum with questions the past few days, but you guys are my go-to source when all else fails!  I've got what I believe to be the original timing cover for my '69 351W.  What's strange is that the area where the oil dipstick tube normally presses into is actually threaded, or has been tapped like something is supposed to thread into it.  Neither I, nor any of the other mechanics I've talked to, have ever seen a threaded dipstick tube; we've only seen the tubes that press-fit into the cover.

I've learned to never say never, especially with Ford, but this has been stumping me as well as most of the "Ford guys" I've talked to in town.  The original dipstick tube for my car was long gone.  I called NPD and Mustangs Unlimited, and neither supplier had any reproduction tubes on the shelf.  NPD's supposed to call me back tomorrow when inventory comes in, but the guy from Mustangs Unlimited said he "thought" the 351 dipstick tube was supposed to be a press fit. 

One mechanic I talked to believed that my timing cover had been threaded by a previous owner.  However, I have my so-called original cover as well as another C8-dated timing cover, and both are threaded.  Looking on eBay, several timing covers appear to be threaded, but I can't ever find a dead on picture of that area.

For some reason, the Osborne Engine manual shows the dipstick and installation procedure for 390 and 428 cars, as well as 6-cylinders, but it doesn't show a 302 or 351. 

Thanks for your help!  I'm open to any advice anyone can give at this point!

[Sluggo]

Is it threaded or knurled to help hold the tube in place?

[J_Speegle]

Have seen guys thread the timing cover to retrofit a braided dip stick line. Never seen a threaded dip stick tube that I recall on a classic Mustang or Ford. Trucks, airplanes - yes

[drummingrocks]

Is it threaded or knurled to help hold the tube in place?

Good distinction.  It really looked threaded to me, like it had been intentionally tapped for some reason.  I'll have to look at it again tomorrow to be sure.  I dug around on eBay in my spare time this afternoon, and I found several companies offering threaded dipstick tubes.  That being said, I never could find a Ford NOS tube or anything like that, so I may just be seeing aftermarket products.

[drummingrocks]

Here's the picture of the timing cover in question.  I called NPD last Friday, and they confirmed that the reproduction 351W dipstick tube is a press-fit, NOT threaded.  This is the original cover for this motor, so I'm trying to think of some way to make it work.

[J_Speegle]

Here's the picture of the timing cover in question.  I called NPD last Friday, and they confirmed that the reproduction 351W dipstick tube is a press-fit, NOT threaded.  This is the original cover for this motor, so I'm trying to think of some way to make it work.

Ok have you test fit the dip stick tube (unthreaded) into the hole. Is it a loose fit?  If its a tight fit then there is no problem if loose then there are a couple of ways to attack the problem I believe that will leave you with a stock looking arrangement

[drummingrocks]

No, I haven't received the reproduction 351W dipstick tube yet.  I did, however, try an original 289/302 dipstick I had laying around, and it literally just fell down into the hole, with no tightness at all.  Not sure if the 351W tube is thicker or has a bigger diameter than its 289/302 counterpart.

[J_Speegle]

No, I haven't received the reproduction 351W dipstick tube yet.  I did, however, try an original 289/302 dipstick I had laying around, and it literally just fell down into the hole, with no tightness at all.  Not sure if the 351W tube is thicker or has a bigger diameter than its 289/302 counterpart.

Guess (in an effort to keep the original timing cover) you will be faced with filling up the gap between the two. A number of ways to attack the issue (once you get the new dipstick tube) none of them are going to be fun but one the tub is inserted and all is painted it should go undetected

[drummingrocks]

I've got several ideas for fixing the tube, none of which I really prefer.  Firstly, my dad mentined getting a small piece of correctly sized brake tubing that would fit or press snugly down into the existing hole.  The brake tubing would need to be slightly flared at the top, so as not to accidentally be pressed through the timing cover.  After it's installed, then the oil dispstick tube could be pressed tightly into the timing cover. Once painted, it should be fairly hard to detect.

The second option is having a local welder weld up the hole, and then redrilling a new hole.  I'm sure this idea would work, but I really don't want to pull the timing cover back off the motor if I don't have to.  Of course, that would be a much longer lasting solution than the brake tubing idea.

[J_Speegle]

Many options from sleeving the tube in rubber, another layer of tubing, epoxy, expanding the tube...... just have to balance out all the opinions and choose.

Good luck with the project

[drummingrocks]

Thanks, Jeff!  Much appreciated!

[drummingrocks]

Well, I can finally put an end to this saga.  I got my reproduction timing cover tube from NPD, painted it along with some other engine parts, and was able to install it in the timing cover.  I guess all along what I was assuming was bolt threads was actually knurled in order to make the tube fit more tightly.  I was able to knock the tube in place, and it fit very tightly, as it should.

My only gripe is that either the reproduction tube has too long of a mounting flange where it bolts to the cylinder head, or the Scott Drake reproduction coil bracket is too short.  When I attempt to bolt the coil bracket behind the flange on the dipstick tube, the coil bracket is way too short to meet the bolt hole.  Anyone encountered this? 

[J_Speegle]

Last one I did all fit very closely to one another (had to really work things) but did get them to barely fit where they should

[drummingrocks]

Thanks, Jeff, that's good to know.  I'll keep working with it.  Hope I don't end up having to slot the bolt holes or anything.