yes, the caps were matching, just in the wrong order. I plan on pulling the filter unit and replacing the check valve spring too, this motor has always had oil pressure issues, terrible when hot and idle.
I was looking at the high capacity pump from XKs, getting together a shopping list. It has a spin on filter from later model.
I had put a 700R4 in the car, but I cannot get the thing to work to my satisfaction, down shifts from 4th to 3rd when I want to go faster than 80. I have all the parts to go to a manual with O/D, may go back to all Jag again. But that is after I get this area sorted out and back together with the new suspension installed.
As a matter of course, replace the OP relief valve: they can look perfect⌠and not work.
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Paul,
When i checked availability, to fit my filter unit, they were NLA. So spring and valve replacement out.
Well, the way to test them is, if the car still has low OP, use a set of pinch pliers to squeeze off the return tube. If the pressure goes up, youâll likely have found the problrm.
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What chassis, sump and filter mount are we working with here?
Mike,
It is a 1966 3.8S. I installed a Johnâs Car transmission adapter for the 700R4. The filter housing from the pictures I have found is from a Series III XJ spin on. I did manage to find a few of the parts on the XKs site for the check valve, but no spring available.
Does your filter mount have ports for an oil cooler? They came with and without. Does it look like the one on the left, or the right?
Mike
This is a confusing statementâŚ
A bolt stretches uniformly from the head of the bolt to the attachment to the nutâŚso it does stretch uniformly along the unthreaded shank and along the threaded portion of the bolt up to the nut.
Did I misinterpret your statement�?
When you are designing for simple tensile stress (rod bolts are also subject to fatigue-life allowable stress reductions I wonât get into here), you have an unthreaded shank of a nominal diameter, and a threaded end, where the diameter at the thread roots is less than the shank, therefore it is the weakest part. It performs like two springs of unequal strength connected end to end, the weaker spring will stretch before the strong spring. The allowable load is proportional to the cross section of fastener, which is smallest at the threads. If you are designing a tensile threaded fastener, you design around the thread root, not the shank. For this reason, very high performance fasteners have shanks that are the same, or smaller, diameter than the minor diameter of the threaded section. On those bolts, the strain is uniformly distributed along the entire shank, not concentrated in the threads. You can see that design in the Crower rod bolt in the photo.
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Yep. The spring analogy is valid but the springs are essentially in series and share the strain as it is applied in proportion to the stiffness of the sections.
I would have thought that the main reason for the reduced shank style of bolt is weight reduction�?
The limiting factor in a (non-fatigue) tensile connection is the stress concentration factor at the root of the thread form so the shank can be substantially reduced in diameter to run at a higher stress and still not be the limiting factor in the connectionâŚ
The big killer in bolted joints is the strain âdiscontinuityâ at the face of the nut as you statedâŚbut this is reflected in the âstress concentration factorâ Engineers should apply to the design.
Mike,
No it doesnât have the ports. I have ordered new rod bolts from Barrett.
If I used the high capacity oil pump from a 4.2 is it easy to use the pick up tube for a 4.2 or just keep the 3.8 tube with adapter as the flow difference wouldnât be that much?
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Yes sir, but even in the static condition you can never overcome limitation of the reduced diameter of the thread root. The cross-sectional area is a function of the square of the radius, so a small reduction has a disproportionate affect in stress at that point. The shank will always be underutilized. When the root diameter is the same as the shank, you can then distribute the strain, the bolt stretch, throughout the full length of the fastener. I was saving the fatigue analysis notch sensitivity and the effects of fully reversing stress for chapter 2.
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Heh hehâŚNooooooooâŚI think I have to dash off and get my appendix removedâŚ!!!
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The adapter/bushing will be fine. As far as that goes, you did just fine with the 3.4/3.8 oil pump, whatâs changing? Same compression, same rpm, same cams? That said, maybe all you can buy now may be 4.2L pumps?
Morning guys, just an update from my original question on reusing original conrod bolts. I bought a set of late model bolts from Barrett, installed them just now with new rod nuts loctited in place with Locktite 262.
Yes you talked me into it, figured I really didnât want cotter pins in there even if they were new using bolts over a half century old.
Also purchased a high volume oil pump that installation is next in the coming week.
cheers and keep safe.
gerard
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Properly torqued, there was no need for the Loktite.
In any case, glad the new standard-style bolts worked: they are completely adequate for any streeter.