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Larry - The crank journals look very good, as does the rod journals. And all bearings Platigauge out in spec. None of the bearings look bad enough to give me the rod knock sound I was getting with the stethoscope down at the oil pan. Sort of disappointing. Was hoping to find a bad-ish rod bearing. But that's not going to stop me from out and out replacing the bearings and oil pump. The sound didn't sound like a wrist pin. So, I really won't know if I fixed it or not until it's all back together and I warm it up the first time.
Bill, I just re-read your last post (#61) and when you say "...all bearings plastigauge out in spec" do you mean they are all within spec or all out of spec? I don't know the specific clearance for your bearings, should be in the .0015 to .003 range, but if this is what the plastigauge showed I don't think you have a rod knock. What was the hot idle oil pressure when you heard the knocking? If your oil pressure was acceptable ( 15lbs or more at hot idle) could you be hearing one or two loose pistons causing "piston slap"? At idle, the two conditions can sound very similar, but piston slap won't affect oil pressure. Piston slap is more pronounced on a cold engine, but still evident on a warm engine. My wife's V8 sounds like someone under the hood shaking a wooden box with 8 rocks in it.
Larry - Yes, I put a dial indicator on the crank shaft to check end play both before and after the new thrust washers. And it was within tolerance in both cases.
Dave - Plastigauged all "within" spec. Oil pressure was low before starting all this. The analog gauge was below 15lbs, but who knows how that really reads. But... the red idiot light would momentarily flash when warmed up stepping on the brake coming to a stop. Now that IS an indicator. Especially because I ordered a new sender, and it did the same thing.
Clyde - You are voicing my worst fears! And not finding the smoking gun is keeping me awake at night. Actually I'm 2/3 of the way into total rebuild, as I did a complete head job, all new head studs, and all of the timing chain tension pads 6 months ago. And... to Dave's question above - I did not see any piston slap indications when I looked at the cylinder walls back then. IF (and that's a BIG IF), I do decide to pull the head again this go around, I'm concerned about honing the cylinder walls and not getting ALL the metal gritty stuff from getting everywhere. Even if I do cover up the bottoms of each piston hole best I can. Your recommendation is not falling on deaf ears!
Knock when warm kind of counts out piston slap, You might see the wear on a piston when it was all the way down in the bore and would look like a scallop wear on the skirt. If you haven't yet installed the rod bearings, push the piston up in the bore somewhat and try to wiggle the wrist pin? How about excessive side play of connecting rod to crankshaft?
I haven't been able to detect any up and down movement in any of the wrist pins when pushing up and down. I do see some side play on all of the big ends back and forth on the journals. But none see accessive. Don't know what that tolerance should be. And I'm not burning any oil at all.
I'm starting to come to the conclusion that by replacing the mains and rod bearings and the oil pump - that in itself will raise the oil pressure at idle and quiet whatever is making the noise. Any engine will make noise without the proper oil pressure.
Hello Bill, I went back on all the information you provided and caught a clue to possible low oil pressure. Back to topic # 65 where it was stated to Dave that the low oil pressure light would come on during braking? Does your oil pan have a metal splash shield to keep the oil in the oil pan during braking? Have inspected the oil pump suction pipe for cracks or splits and for proper fit to metal splash shield?
Yes the splash pan is there and I've had it apart and cleaned it. But... I will inspect things more closely as to your other suggestions. Thank you for giving this your careful, thoughtful consideration. MUCH appreciated. I'll keep you posted.
Larry - and to your point, both the input and output O-rings of the oil pump were brittle and broke easily when I poked them. I tried to get them out to try to match them as the new pump didn't come with them in it. So... maybe they weren't making the type of seal they were supposed to be making. 47yo O-rings are hard as a rock! I do have new O-rings on order with SNG Barrett. I wish they had told me they don't come with the new pump when I ordered it from them before. You may have led me to the "smoking gun, ah ha" moment I've been looking for!
I suspect that you do not have the classic "rod knock" I have been there, more than once!!
Unless the bearings are really bad, they do not knock at idle or even at speed when under load. But bacxk off on the throttle and go in coast mode and then they sound off, big time.
Although your engine has chain drive cams, I am thoinking there. I had a couple of OHV cars that developed bad chains Indeed, they noese was mucxh liek a rod knock
And, at one time, a fellow eitha flat head ford V8 had a rod knck like sound. No chain on that engine, but, a bad cam gear was the answere.
In closiing ty the coast knock idea.
One other remains Piaton slapl but from your post, i dobt it.
What I am thinking about is a air ( suction) leak before the pump . Take the suction pipe to the full sink of water and place thumb or cork over end then place pipe into water so as to cover any joint. Blow into pipe and you should not see any bubbles.
Jaguar had troubles like this back in the 3.8 days.
New bearings installed and torqued down, new oil pump and O-rings installed. Oil pan back on. I used a plywood board to make a 18" x 8" platform for my hydraulic jack to raise the super heavy front suspension back in place. I unscrewed the jack's OEM round plate and installed the plywood inplace. Worked perfectly. So assembly back on and tighten up, mounted brake calipers and shock absorbers. Used jack with platform to raise the steering rack into place and started connecting it back up. Only a few days away from starting her up.
Jack with platform Raising front suspension in place
Here I am late in posting. or did I post this before. ?
The noise you describe, does not connote a rod knock to me, Loose bearings, unless they are real bad are silent at idle. And silent on load.
It is when you release throttle that they sound off.
Decades ago, circa 47, school chum and T mentor, Billy and I were in my T just past Alamogordo on the way to Ruiidoso, New Mexico. A gentle climb. Then a down hill. BZZZZZ / Immediate recognition.
Well, we pulled off, Dropped the pan. Refit the babbit. Decided to scrub the missiona nd go home. Wise. An autopsy found the line that tookl oil tot he front was busted. So, it would oil on level ground. but not on an up hill!!!
I think your knock lies elsewhere. timing chaion comes tomind.
UPDATE - ENGINE - replaced rod, main and thrust bearings. New oil pump, new O-rings, new gasket, then pan back on. New oil and filter. Started engine up (no coolant in it yet) and oil pressure came right up to the 80lbs mark. No strange noises Still up on jack stands and engine support bar.
UPDATE - FRONT SUSPENSION - Have completely rebuilt it. New upper and lower bushings, upper and lower ball joints, new tie rod outer ball joints, used previous springs (only without the three nylon spacers - as I wanted it a bit lower), and rebuilt steering rack assembly that I got from Andrew Specialties. Installed all up into place and connected it all up. Never pulled calipers apart; just hung with safety wire so I didn't have to bleed them.
Put on new drive belts, installed electric fans back on, radiator with new hoses, put A/C condenser back in. I never disconnected the hoses so didn't need to discharge and recharge the refrigerant. Put the hood back on. BTW - I took the hood off by myself and installed it by myself. The trick to that is remove the hood inner headlights and buckets and you have easy access to the three 1/2" bolts that hold the hinge to the hood. Then carelully lift it off. It CAN be done. I've done it twice that way now.
ON THE ROAD AGAIN - two days ago put on the road. Steering was REALLY WONKY! Took me hours of troubleshooting. I'm embarrassed to say the solution was way too simple. I installed the tie rod outer ball joints in the TOP of the steering arm. In my defense almost all of the pictures in the manuals show the tie rod ball joints facing down. Yes, I should have noticed when I tightened them up that way, they were not drawing down into a taper - but I didn't. Even though they were tight static on the garage floor, they had a mind of their own when driving! Once I figured out they go in from the bottom (and drew into the taper just fine), adjusted the toe in (ballpark 3/16"), it drove the way it was supposed to. Lightening bolt moment! Slap me across the head moment! Now I'll drive a bit to let things settle in, then bring it to get the front end aligned.
The engine is another story - the oil pressure never drops below the 20lbs mark on the analog gauge (and before it dropped halfway to between 0 and 20). Yet the red idiot light still comes on when warmed up and I come to a stop. Just briefly, as before, but on none-the-less. The "knock" is still there but much more muted than before. I have to drive it more to gather more data. More than a little disappointed there!
Good Job, Bill!!
I'll assume you drove it around the block to settle it Before you torqued the lower wishbone bolts(?)
Otherwise (as many of us have learned the hard way) all your money and hard work on that is wasted and you'll have to do it again in about 3 years.
I know you're looking SO forward to that-NOT!
It IS a great feeling to have it back on the road, isn't it!
Congratulations!
(';')
