D25 Engine Rebuild thread

[Don Coatney]

I am not the expert but I did find this.

Gives the proper amount of stretch to get the proper amount of torque.

Page 37 in the 5th paragraph

http://video.arp-bolts.com/catalog/ARPCatalog.pdf

So how does it help with rusting solid?

Thanks. Good information. If the bolt shank is not undercut any moisture will cause oxidation. Many head bolts do screw down into the water jacket so moisture is present. This moisture does cause oxidation and this caused the bolts to "grow" thus causing expansion that will cause rusting solid.

[bamfordsgarage]

I got my engine parts back from the machine shop Friday and they sure look purdy!

The ring gear teeth were badly worn in three areas — not so much as to make starter pinion would skip, but enough to want something done about it. I removed the gear, dressed up the rough tooth edges, and reinstalled it 1/6 of a revolution from the original location. Should be good for another 90K miles.

Photos: Worn ring gear teeth re-positioned; For a short time I drove an ultra-rare 12-cylinder Mercury Sable wagon; Cylinder head shaved 0.040-0.049" (was warped 0.009"); Valves ground and ends faced; lifters faced both ends.

Second batch of photos to follow shortly.

[bamfordsgarage]

There is a very unexpected wire, roughly the size of a coat hanger, visible and wiggleable in the water jacket, along the valve side of the block. See photo #5 — can anyone tell me what this is?

Photos, batch two: Camshaft polished and pretty; Crankshaft likewise polished and pretty, main and rod journals 0.010 undersize; Cleaning out the head bolt threads, cylinder walls and valve seats machined and ready to go; Cylinder #6 plug is the first part reassembled!; Mystery wire in water jacket.

[Niel Hoback]

We alll find those pieces of wire inside the water jacket. They are, or were, part of the sand casting mold. If you leave it in, it won't hurt anything.

[Don Coatney]

Down here in the states we use a tool called a tap wrench when using a tap. I have never tried channel locks.

[bamfordsgarage]

We're technological trend setters up here. Surely you're familiar with the work of Red Green...

Edited January 29, 2012 by bamfordsgarage

[Joe Flanagan]

I found the wire in my block too when I was flushing it out. Just left it in place.

[Don Coatney]

We're technological trend setters up here. Surely you're familiar with the work of Red Green...

We have Tim "the tool man" Taylor and we have you beat on roof racks. These are actually natural gas bags that fuel these cars.

[JerseyHarold]

We're technological trend setters up here. Surely you're familiar with the work of Red Green...

Red Green is certainly on the cutting edge of technology. He has a following here in the States, too. There are lots of Handyman's Corner episodes on youtube, cleverly done and worth a look.

[Joe Flanagan]

Hm. Normally you'd find the natural gas bag sitting up front in the passenger seat.

[kbuhagiar]

Down here in the states we use a tool called a tap wrench when using a tap. I have never tried channel locks.

Out here in the West we call those channel locks Vise-Grips!

[T120]

Out here in the West we call those channel locks Vise-Grips!

AKA,tap wrenches

[bamfordsgarage]

We all find those pieces of wire inside the water jacket. They are, or were, part of the sand casting mold. If you leave it in, it won't hurt anything.

Thanks Niel and Joe. I figured it must have been something like that. After further reflection, I expect they gave more structural strength to those isolated extremities of the packed sand core prior to and during the pour. And they were likely heavier gauge before 64 years of immersion.

[Don Coatney]

Out here in the West we call those channel locks Vise-Grips!

You are correct Vice-Grips are what I meant ot say.

[bamfordsgarage]

Still waiting on my bearings etc. to arrive from Terrill in Texas... while major reassembly is on hold, I've been puttering with frost plugs and fuel pumps.

My replacement frost plugs were bright, shiny, modern — and looked hideously out of place in my engine. I've generally been content to let rust happen naturally but this time went looking for a quick fix.

The project is complete and I'm reasonably pleased with the results — while the plugs don't particularly match the block colour, they look suitably old and like they've been in place for years. Installation was with Right Stuff sealant and a vigorous clobber dead center of the plug.

I'm sure there are hundreds of forum members secretly anxious to make their new parts look rusty and decrepit. Here's how (Photo 1 below) 1. Belt sander vs cad plating; 2. Sandblast; 3. Vinegar etch (absolutely essential, sandblasting was not enough); 4. Hydrogen Peroxide 3%; A wee bit of gun blueing was used later to darken a little further. I expanded on the basic procedure outlined at this link: http://www.instructables.com/id/Produce-a-Rich-Rust-Patina-on-Iron-and-Steel-Safe/

And now some fuel pump complications: Last spring I bought a double-action fuel pump from Antique Auto Parts in Arlington, TX, with the intention of replacing my single-action pump and enabling my vacuum wipers to reach their full potential (and packing the original pump along as a spare). Compared the two pumps today and there is a major difference — while the mounting flange and pivot-pin location are identical, the arm itself is a different style and offset 1/4"+ from the arm on my original pump.

One option is removing the pivot pin and swapping the drive arms. This entails the risk of unexpected problems and makes swapping pumps at-the-roadside much less convenient. Another option is sourcing the correct pump elsewhere and finding a new home for this one. There is an application list on the side of my new pump, Photo 5 (that I understood listed the models this pump was installed on new, though it would still fit mine. Oops.)

My other fuel pump puzzle relates to NOS pumps — is there a way to tell if they are ethanol-fuel susceptible (we have up to 10% in our gas) or is it best to assume the worst and replace the rubber parts before use?

Anyone with the correct pump willing to sell or trade? Anyone else interested in my double-action unit? Other comments?

[Don Coatney]

Were it me, I would buy new rubber for the NOS pump. Why take a chance on a leak. We all know what can happen when rubbers leak.

[Young Ed]

My other fuel pump puzzle relates to NOS pumps — is there a way to tell if they are ethanol-fuel susceptible (we have up to 10% in our gas) or is it best to assume the worst and replace the rubber parts before use?

Yes rebuild the pump before use. Ethanol eats old fuel pumps. I've never seen that particular style of arm before but I have seen a few varieties and they all worked just fine. I suspect even with your 1/4 inch variance that it will still contact the cam and work correctly.

[greg g]

I second Ed's position. I believe the arm on the stock pump is not in contact with the cam all the time. I would try a test fit while you have the sump off and see how the arm rides the pump actuator on the cam. As log as it moves through its high point and relaxes, it shold work fine. I believe you might actually see an air gap on the original pump when the cam is rotated to its low point in relation to the pum arm.

[bamfordsgarage]

Gee, if only there was some consensus about whether to rebuild the new fuel pump...

Greg, your take on the pump lever was right on. When test-fitted the lever free play was eliminated and the arm made contact at the right point to produce the expected pumping noises. The new return spring is much stiffer than the old one and very hard to move by hand.

I see Antique Auto Parts Cellar in MA offers rebuilding kits that have been well reviewed by forum members. Can anyone suggest alternate sources that I might check before placing an order?

My parts order from Terrill in Texas arrived today and I am most impressed. All items appear to be correct, and the Priority Mail shipment was only six days in transit. Canadian readers may be interested to learn the postage was:o $40 (flat rate box) and the parcel arrived with zero GST or duty owing.

The order included cam bearings — more on spec than for any specific reason. Test fitting these on the camshaft seemed very sloppy on each journal. I slid the cam into the block to check the fuel pump action and found no discernible bearing clearance, even with use of a pry-bar (Photo 5). So I am considering just leaving the old bearings in place. My manual says they generally do not wear appreciably. Does this seem to be a reasonable approach, or am I likely to see considerable compression/diameter reduction after pressing new bearings into the bores?

Photos: Terrill order as ordered (parts numbers available to those who want them); Rod bearings travelled from Canada to the US and back again; New timing chain is a lot more limber than the old one; Camshaft gears old and new; No noticeable play in the existing cam bearings.

[Don Coatney]

Sloppy cam bearings are the number one cause for low oil pressure in high mileage Mopar flathead engines. Replace them.

[Joe Flanagan]

Chris, regarding the rebuild kit for your fuel pump, I wouldn't look any further than Antique Auto Parts Cellar. They're helpful and they ship promptly. I rebuilt my pump with their kit and it turned out really well.

What Don said about the cam bearings seems to be a cardinal rule for flatheads. Once they fail, everything else follows pretty quickly. It's not worth whatever you'd save by using the old ones.

[Jim Yergin]

Chris,

If I remember correctly, the cam bearings have different diameters based on location. When you checked the clearance were you doing it with the bearing at the proper location on the camshaft? I am sure you did but thought it would be worth mentioning.

Jim Yergin

[PatS....]

The order included cam bearings — more on spec than for any specific reason. Test fitting these on the camshaft seemed very sloppy on each journal. I slid the cam into the block to check the fuel pump action and found no discernible bearing clearance, even with use of a pry-bar (Photo 5). So I am considering just leaving the old bearings in place. My manual says they generally do not wear appreciably. Does this seem to be a reasonable approach, or am I likely to see considerable compression/diameter reduction after pressing new bearings into the bores?

If you have the engine apart now and do not replace them, Mr. Murphy will have you do it in a much less comfortable and much more expensive location in the very near future...that's just my experience.

[Young Ed]

Sloppy cam bearings are the number one cause for low oil pressure in high mileage Mopar flathead engines. Replace them.

I have heard this many times before too. Worn cam bearings cause low oil pressure to the main and rod bearings and bam no more engine.

[bamfordsgarage]

As usual, replies all over the map with no hint of consensus.

My point is the new bearings are a sloppy rattle fit on their respective journals when loose. It's really hard to imagine they would crush up to a proper fit once pressed into the block. I'll take some good measurements in the AM and report back.

In the meantime, have any of you replaced cam bearings that had a sloppy fit when loose but tightened up to spec after installation?