Hello Cadillac friends,
This concerns my 346 from 1948.
Runs well and oil pressure of 30+ on dashboard.
Annoying engine tick when the engine is warm is the issue I want to solve.
I have read many Posts about this topic which is very usefull.
Several months ago you gave me suggestions on how to solve the engine tap problem (only when it is warm does it tap). With your help I have made a checklist that I follow to solve the problem. I've done the following:
-Muck removed from engine pan (2cm thick) and engine cleaned (Cleaning oil and adaptive).
-Oil supply to valves checked -> oil gets to the valves
-lifter blocks removed, all 16 filters cleaned and installed.
Before I close the engine for testing, I have the following questions:
1. It is hard to turn the engine without spark plugs. I expected this to be easier. Is this correct or should it spin smoothly?
2. I see that some lifters are not turning when I run the engine (via the starter motor). Is that because there is not yet oil everywhere after cleaning or could this also have another reason?
3. The engine had a external oil filter which I have now removed (input from main and output to crankcase). This is because it is a bypass, not all the oil is filtered. Isn't wise to get the oil to the lifters through a filter? (Do anyone have experiences, also in terms of oil pressure loss?)
Please give your advice and experience.
Regards,
Jaap
Jaap,
Having owned Cadillacs all of my six decades of driving "life," I suggest that your problem may "solve itself" once you get the engine running and under load. I have noticed that taking long highway trips with older Cadillacs actually improves their functioning and performance. It may have something to do with the metallurgy or the way the valves seat, or perhaps carbon in the seats and/or valve stems in the combustion chamber; however, as I stated above, my older model Cadillac engines seemed to thrive on long road trips, and annoying mechanical noises and concerns simply disappeared. I realize that my response will not verify just what causes the ticking, but I've experienced this problem, and in my estimation based on what you've described, the ticking may simply disappear once you get the car on the road and drive it. Hope this helps, James
I'd get an occasional tick with my 1937 Lasalle until I added some Marvels Mystery Oil during an oil change. Went away and the engine sounded great!
Tim, I'm also a great fan of Marvel oil, and using it as a potential "cure" for Jaap's tick is a great idea. I also have used it with terrific results with hard starting (when hot) Cadillacs in the gas tank during the summer months. My theory is that the Marvel oil "ups" the boiling temperatures of modern gasoline and decidedly causes these older engines to start far more easily. James
I'm not sure how far you have come with closing the engine up. Each lifter should be primed with oil before installing in the carrier. Once the lifters are in place hook the oil feed lines but do not tighten. You can then spin the engine with spark plugs out until you see oil coming out of the fittings then tighten them up. This procedure forces the air out of the system. Harry
Jaap,
Hi....A, number one question in my book would be did you check the measurements between the heel of the cam lobes to the valve stem tips while you had the blocks out? That would be my first choice other than checking oil pressure at various locations by fabricating an in-line "Tee" fitting. To me, the oil filter is Waste of time if you just change it more often. When you said you "cleaned" the lifters, I assume you disassembled them completely, cleaned, and re-assembled. Hopefully they went back in their respective positions in the lifter blocks...
Bobby
Thanks for the suggestions guys.
Yesterday I closed the engine again and started it. It runs not stable and leaked a bit through the exhaust manifold. After a few minutes there was a screeching noise that looked like a rotating object that was not getting any oil. (or slipping V-belt) I turned it off immediately. It wasn't the generator or the fan. (disconnect both V-belts)
Oil level is just below max.
Do anyone have any idea what this could be?
@bobbie: I haven't checked the 3 "because nothing has been renewed at any of the valves and lifters. I want to do that, but I haven't read anywhere yet what to do to get it within the tolerance (not in my 1948 Shopmanual). I have also read your previous post on this topic and understand that this is an important element.
Yes, I have disassembled them completely, cleaned, and reassembled them, piece by piece. I oil them before reassembling in the Bracket. I oiled also the plunger in the body before reassembling. (I have Unit-tpe lifters see attachment)
Screeching is a belt unless its internal.
Jaap,
Having nothing renewed has no bearing on that clearance spec because it changes as valve stem tips wear and valves pocket into the seats. When you had it open would've been an ideal time to measure. At least you could have eliminated another variable....
Bobby
Quote from: 55 CDV Fan 82 on December 23, 2020, 02:36:59 AM
Screeching is a belt unless its internal.
I once installed a new water pump and one of the bearings on the new pump was bad. That made a terrible screeching noise instantly upon starting. I turned it off immediately and the snout of the pump was EXTREMELY hot. It wasn't on a 1948 346 though.
My point is a high pitched screech, which you feel is metal-on-metal, will make heat fast so one of the infrared pyrometers can be very useful in determining the source of the noise even after you shut it down immediately. I would be very reluctant to start it if you think a high pitch metal-on-metal was an internal issue.
Once you resolve the screech: If you think it's in the valve train one trick is to remove one spark plug wire at a time until you notice a difference in the sound. You can at least narrow down where it's coming from. If you go through every plug, only 1 wire off at a time, and it doesn't change it's also evidence the issue may be somewhere else. That can also work with a rod knock.
Good luck.
Scott
Quote from: Bobby B on December 23, 2020, 07:28:49 PM
Jaap,
Having nothing renewed has no bearing on that clearance spec because it changes as valve stem tips wear and valves pocket into the seats. When you had it open would've been an ideal time to measure. At least you could have eliminated another variable....
Bobby
Hi Bobby,
You are right and I need to open the motor again for the screeching noice, I want to be sure everything is normal at the valves. (I hope it's). My question is
how do I change the 3" space, I can't find any documentation on this. If you can help me on this, I would be grateful.
Quote from: 79 Eldorado on December 23, 2020, 09:20:10 PM
My point is a high pitched screech, which you feel is metal-on-metal, will make heat fast so one of the infrared pyrometers can be very useful in determining the source of the noise even after you shut it down immediately. I would be very reluctant to start it if you think a high pitch metal-on-metal was an internal issue.
Thanks for the tip Scott. My main concern now is to locate the source of this. Nothing els (exept the lifter disassembly; cleaning; assemble) is changed on the engine. I disconnect both belt to eliminate the belt screeching. With this the waterpump and generator are also disconnect so that will not cource the problem I gues.
I'm open for other suggestions.
Jaap--
This is truly suggestion, and I'm hoping others will join in--- I have heard of distributor shafts that, for lack for lubrication will squeal and seize... the problem, I think having to do with its placement and the possibility that the oil gallery to the bearing is clogged. Again, just a "thought," and I'm hoping others will continue the conversation. Clearly, if you can avoid dismantling the entire engine, that would be great. Happy holiday. James
Quote from: wustjaap on December 24, 2020, 01:02:45 AM
My question is how do I change the 3" space, I can't find any documentation on this. If you can help me on this, I would be grateful.
Jaap,
Hi. You can't. It's a time consuming task and usually done when a "Valve job" is in order, which on a flathead, is basically a teardown. Once the seats are changed (or re-cut) and new (or existing re-cut) valves are installed, every valve/spring has to be put back together, minus the lifters, and that distance must be checked on each and every valve. For checking purposes, I use lighter springs to make it easier. As long as they have enough tension to hold the valve fully closed, any spring works. It usually involves removing the valves again after measuring and grinding the valve stem tips down to get the proper 3" clearance needed. New valves are cheap and there's usually enough meat on them to cut down to get the proper clearance. It's a tedious and time consuming job to get it right, and I can't tell you how many horror stories I've heard regarding Flathead rebuilds where the machinist/ assembler never performed this critical step and the engine had to be taken apart again. If it's an existing situation and it's not WAY out, I would let it fly, but it should be checked first before tearing stuff apart just because it'll eliminate that as a culprit regarding your ticking problem. An older Flathead has some ticking noises anyway, so if your oil pressure seems OK and it runs good with decent power, I would either live with it or be prepared to have it rebuilt.
Bobby
One of the tenets of "systematic troubleshooting" asks is there any recent work on or about where the defect resides before the defect occurred. Usually, that work's related to the cause, something done or left undone. So probabilistically, the squeal is "most likely" related to your recent efforts, not something "new". Yes, it's possible you got oil on a belt, pulley, or something minor but that's related to the work too.
Might help to know what the age / mileage is on this motor and what the overall condition of it is. Tell:2cm is nearly an inch of sludge, so not exactly clean block and lube system and smacks of a life of poor maintenance and sitting. Can't reverse that with an additive, unfortunately.
Sometimes, one just has to bite the overhaul bullet, if the desire is perfection. That's even not a guarantee as we've seen with some post lube rebuild issues.
I think you're bettor of WITH the partial filter since the sediment was disturbed. Suggest you change the oil again right after you get it back running after it warms up. Any dislodged sludge will find a resting spot in some passage and wreck havoc. If it's had a life of non-detergent oil and you introduce modern detergent oil, it's a recipe for these problems.
As mentioned, sometimes, those little imperfections will go away, and better left untouched, but which ones to treat is a conundrum.
One other thing which came to mind when someone mentioned detergent vs non detergent oil is everything they've taken out of the modern oil in the past 2 years. I would need to verify API standard per allowable additive level but the oil standard as updated in either 2018 or 2019 resulted in a further reduction of some of the additives which act as high pressure point lubricants. At the time I heard Ford was filing against one of the large oil companies because the tip pressure on some of the rockers was high enough that failures started to occur which Ford believed were as a result of these reductions. In general there has been a lot of discussion around the issue with rebuilding any engine but especially anything which uses a flat tappet cam. I'm now using a 1/2 bottle of STP additive when I do a standard maintenance oil change and any significant rebuild should probably use break-in oil which has a higher Zn and Phosphorus content. I didn't do a lot of research regarding which additive is the best but I've been using "STP NCB65148 Zn additive" from NAPA.
As Jim mentioned normally when a new issue occurs after a repair it was something touched during the repair; even if it wasn't something conscientiously touched. I was also thinking the same but I didn't mention it because we really didn't know well how long things were sitting and the overall condition other than the 2cm of sludge... anyway the rule is more times true than not in my experience.
Removing the belts for a quick check was a good idea.
Scott
All, thanks you for you response
First I will celebrate Christmas 🎄 (on covid-19 distance)
All, happy holidays!!!
Merry Christmas. I sent you a PM in case you want some good documentation.
Scott
Thanks guys for the suggestion and Best wishes for 2021.
At one point I thought the screeching noise was the starter, but when I reassembled the engine screeching noise does not appear and it started fine and ran well.
The result of my actions is a clean engine of which I know the lubrication system is working properly.
BUT: The tap/tick is still there but is therefore not caused by a dirty engine or mallfunction of the oil system.
Easy first step is to change the oil and add some Marvels Mystery Oil.
First I want to rebuild my Carter carburetor and fuel pump. (ordered 2 rebuild kids for it.)
@Bobby: I measured the 3" distance and found it to be a little less than 3" on all lifters. That would mean that I have to remove something from all valve stamps and the head has to be removed for that. I first want to prepare myself well for such a job ;). I am afraid that more pieces will break (mallfunction) when I remove the head.
Thanks for helping..
Jaap
The 3" check gauge is just a check. The actual clearance required is 0.030 to 0.070. Most likely you are fine. To check the clearance you have to get the oil out of the lifter.
Quote from: Brad Ipsen CLC #737 on January 04, 2021, 09:51:22 PM
The 3" check gauge is just a check. The actual clearance required is 0.030 to 0.070. Most likely you are fine. To check the clearance you have to get the oil out of the lifter.
Brad, Hi...If we're talking about the same thing, the 3" distance is measured from the heel of the cam lobe to the valve stem tip, which can only be measured with the lifter blocks out, and only corrected with a Valve job or grinding of each individual valve stem tip, IF you were lucky enough that the clearance is less than 3'', which would be in your favor of stem tip grinding only. Isn't the clearance that you're referring to the lifter's actual limits of travel? So if the 3" clearance is beyond those limits from the start, the lifter travel cannot compensate and that's possibly one issue that could cause some problems. Am I missing something? I made sure that my 3" measurement was dead on, along with dis-assembling, cleaning, and checking every lifter. My Flathead sounds like a sewing machine. You can Barely hear it running......
Bobby
Bobby, the 3" clearance check is valid only if you have new cam follower and hydraulic lifter assemblies, if they are used (worn) or refurbished (reground) then setting the clearance to 3 inches may be in error. The Cadillac service manual says to measure and set the lifter to valve stem clearance to the values that Brad provided.
Tom Beaver
Not sure why Cadillac doesn't state that there is a tolerance on the 3" tool. The tolerance is the range that the lifter is able to accommodate. I'm sure the actual amount it can accommodate is actually more the what's stated also. Good engineering would always allow for a little more. This all is implied in the 1940 shop manual twice. Once in paragraph 15 in the Engine section and again in 16.4. The first reference states: "If Tool J-1055 is not available, it will be necessary to install valves, valve springs and lifters and check clearance between stems and lifters, which should be .030-.070 inch." My reason for commenting is to make sure the original poster does not do any extra work that is not needed. In fact he could have checked the clearance with the lifters in place although that may have been really difficult because of oil in the lifters.
Quote from: Tom Beaver on January 05, 2021, 11:51:30 PM
Bobby, the 3" clearance check is valid only if you have new cam follower and hydraulic lifter assemblies, if they are used (worn) or refurbished (reground) then setting the clearance to 3 inches may be in error. The Cadillac service manual says to measure and set the lifter to valve stem clearance to the values that Brad provided.
Tom,
Hi. I'm not following your theory on this. I checked my original Cam on "V" blocks which luckily turned out to be in great shape, so I opted to use the cam rather than a New China made one, have mine re-ground and/or sprayed, or paying big bucks to have one cut from a billet. Now....I had brand new guides, springs, oil seals, and Valves installed along with the valves seats cut. Now that that work was finished and the valves ready to be installed, I used the tried and true method of the 3" clearance (using a micrometer standard) between the Heel of the Cam Lobe and the Brand New Valve Stem Tip. Tedious yes, but worth it. With all that new work being done, wouldn't you agree that the 3" clearance is what you're shooting for if the lifters all check out after being dis-assembled, checked, and re-installed on their original lobes following the same wear pattern as before? My engine is as quiet as a Brand New Honda, so I must've done something right. Idling at 375 rpm you could put a glass of water on the air cleaner without a drop spilled.....
Bobby
I don't know this particular engine but if it's impossible to adjust without removing the head and if there's a little too much clearance, and especially on only a single valve, couldn't you get an adjustable pushrod, determine the proper length to achieve the proper lifter pre-load, and then order a custom pushrod in the length to have the proper pre-load? On an adjustable set-up you would normally tighten down until you can tell the preload is proper by spinning the pushrod in your fingers. It seems like the same check could be done here with pushrod length change until it was correct. Everything posted seems to say that would work here as well.
Obviously you need to make certain the rocker tip maintains the proper geometry with the valve stem end but the tick is likely a matter of no more than 0.010 to 0.020" I suspect.
One other thing which I don't think anyone mentioned was a small exhaust leak can often sound like a valve train tick.
I did read through the entire thread but most of it was around a week ago so my apologies if I missed something by memory.
Scott
The 346 a Side Valve engine, so no pushrods.
Bruce. >:D
Quote from: The Tassie Devil(le) on January 06, 2021, 08:50:11 PM
The 346 a Side Valve engine, so no pushrods.
Bruce. >:D
Aha! Thanks Bruce :)
As Brad mentions, the 3.00" dimension is a quick and dirty check on new parts and will get you pretty close. It is best to set the valve length to the center of lifter travel, just like all the other hydraulic lifter engines. Just takes some time to measure dimensions with each lifter at full travel and fully collapsed. As long as you are somewhere in the travel zone you should be good unless you are right on the end, either way,
Bobby, my comment concerned the resurfacing of the cam followers or I think Cadillac refers to them as the valve lifter bodies. I have had all of mine resurfaced, and in doing so, changed the overall valve lifter dimensions so that the 3 inch clearance check is no longer valid.
Tom Beaver
Quote from: Tom Beaver on January 09, 2021, 04:54:49 PM
Bobby, my comment concerned the resurfacing of the cam followers or I think Cadillac refers to them as the valve lifter bodies. I have had all of mine resurfaced, and in doing so, changed the overall valve lifter dimensions so that the 3 inch clearance check is no longer valid.
Tom,
Hi, If you resurfaced the lifter bases, it shouldn't change the travel limit of a lifter. By removing metal from your lifter bases, you just shifted your parameters of your lifter travel limit. If your valves were pocketed a bit from wear, you might get lucky, but I would think that the only way to compensate would be through the valves stems being longer, by X amount removed from the lifter base. I guess in your situation the 3" clearance really goes out the window, and you would need to check it in situ....
Bobby
Bobby, what I did was use 38 - 40 lifter bodies which have a deeper recess for the valve plungers and then I used new or late model 41 - 47 lifter plungers which have a shorter upper section. This makes sure that when the two are assembled there is plenty of clearance between the top of the valve plunger and the valve stem. Then I place the assemblies in the lifter blocks and at each valve I measure the clearance between each lifter plunger and the valve stem and record the numbers. I then machine a piece of shim stock (tubing) that has an OD the size of the upper part of the lifter plungers and an ID that is equal to the OD of the lower section of the lifter plungers minus enough for a press fit. I then cut pieces off this tubing to shim the length of each lifter plunger. The length of each shim is calculated from my clearance measurements to make the clearance between the lifter plunger and valve stem equal 0.050". This places the lifter plunger in the middle of specified clearance range 0f 0.030" to 0.070". I don't have to do any grinding of the valve seats nor of the valve stems to adjust the valves, you can do it with the heads on. This may sound complicated but it's fairly simple, it just takes time to take the lifter blocks in and out, position the camshaft and make the clearance measurements. It's certainly much easier with the engine out where you can work on it.
Tom Beaver
I'm going to ask a question here. I'm in the process of rebuilding my 1940 331. I have purchased a new cam, lifters, springs, valves. When I get the block back. I plan on measuring the 3 inch distance like the Manuel says. I'm I wrong?
Thanks Wayne
No you are not wrong but the 3 inch dimension is based on the cam and lifters being dimensioned exactly like Cadillac designed them in 1940. If you understand where this dimension comes from then you can correct for any deviations in your new parts from Cadillac originals. Hydraulic lifters take up the slack in the valve train with a column of oil between a plunger and a cylinder. In the case of the flathead the designed height of this column of oil is .030 to .070 inches. Quite a narrow tolerance compare to later designs such as used in the 1949 331 OHV engine. Assuming all original parts the 3 inch gap between the valve stem and the cam results in that height of oil. I have not checked it but I would assume it puts it at .050 inches of oil (middle of the tolerance range) or with no oil in the plunger you would have .050 clearance. So this gives you an alternate method to verify that the plunger will be within its range and able to maintain zero lash when running even if the cam and valve lifter deviate from the original dimensions.
Hi Brad
So, If I have this correct. I need to put the lifters in dry. check with the cam lobe on the reverse side and check the clearance between the valve and lifter. Simple
Simple, the only problem it is a pain to do because of the little spring on the plunger. What I have done is take an old plunger and remove the spring. You would want to compare it to your new plunger just to make sure that part is the same dimension.
Hi Brad
I will check my old lifters to the new lifters. If I have any questions I will get back with you.
Thanks Wayne