TR2/3/3A problems getting the engine to run correct

[sp53]

I have had problems getting the engine to run correct on this tr3 ever since I tried to drive it after a 20 minute break in at 2000rpm. I put the new rocker assembly on and that quitted the engine, so I could think clearer.

The problem is a rough running engine as I give it more fuel. I have it idling 900 and it sounds great at idle, but when I push on the gas the engine shutters and pulses slightly as I go through the RPM rang to 3000. I replaced the coil and distributor, but the problem is the same. It could be both distributors are worn out because they are original.

The one thing that is freaking me out is when I set the lifters. I set them the way the Haynes manual suggest with an opening sequence of one valve and the setting of another when the valve is close. Well what I notice is number 1 intake hardly moves. The spring just moves just a little on opening say maybe a 1/8 of an inch all the other valve springs move more freely and open maybe 3/8.

The only thing I can think of is the cam is flat and will not force the spring open. The head was rebuilt at a machine shop and I paid top dollar. I have no experience with valve springs and their movement, but it would seem they should have the same movement. I did used the old cam shaft after I eye balled it over good 5 years ago i think.

Does anyone have a suggestion to help narrow this problem down more? Part of me wants to purchase a new distributor from BPNW and the other part wants me to pull the cam out. There are only about 10 miles on the engine

desperate Steve

 

[Frank Canale]

just throwing out an idea but you could check cam by measuring rocker lift with dial indicator. No need to remove cam to check for worn lobe. Compare all 4 one to another. Frank

 

[bobhustead]

Check the valve lash on #1 by turning the engine by hand, watching the exhaust valve open and close, the intake valve open and close, and continuing to turn the crank until the timing mark and pointer are aligned. This is TDC compression stroke and the lifters will be on the bottom of the cam lobe. Set the valves on # 1 here and see if you still have the insufficiently short valve train movement. I set my valves this way, with the timing mark opposite the pointer on 2 and 3, of course.
Bob

 

[sp53]

I think I can get a dial indicator at HP, but I have no real experience with setting one up on an engine to read the lift. It is probably easy, but I have never done it. The more I think about it, the cam is probably shot because there is no real time for the valve to stay open from what I see without the valve cover.

I really want to get lucky and have someone say that I cannot tell for sure just by looking how long the valve is open or if this could cause the stumbling. the poor running-is- kinda like there is no oil in the carbs or something. Once I had a miss that was caused by the carb bowl being partially plugged and itwas like this some, but I do not think so because they are recently rebuilt, but heck better than the cam.

Maybe it is the distributor and the 2 that I tried both have bad vacuum advances. I do have another tr3 that runs good with good dizzy, but I do not want to remove it just for a test. I am just cam shaft ignorant and unsure how to check them without taking the cam out and asking around and showing it to someone. I kinda remember taking a cam into a speed shop once and they said those cams on a tr3 are basic and do not worry it will work fine and he did that by looking. I am curtain I have the lash correct Bob and another check to see if I have it too tight or lose is good advice, before I am done I will check again. I have done it your way also.

shattered steve

 

[Stevenry]

When I noticed two valves not opening much during a valve adjustment, as much as I didn’t like the prospect, geometry ruled, and it was indeed two flattened cam lobes. I replaced the cam with the performance cam from British Parts Northwest, and the car is running great. The rattle/knock I was trying to identify is gone. I had never gone so deep as to replace a cam shaft, but it was certainly doable, interesting, and ultimately satisfying. I also listened to a Stephen King book or two on Audible during the process. The dial gauge was easy to figure out, and the Rusty Beauties YouTube were helpful.

I found YouTubes confusing regarding timing the camshaft, but the instructions that come with the camshaft I bought explain it clearly in a few sentences.

Steve

 

[sp53]

Thanks Steve yes I am afraid so also. I am so cheap that I always gamble on outcomes. Did you leave the engine in the car? I wonder how flat they need to be before they are a problem. Could you visually see the flatten lob after you pulled the cam.

zzzz steve

 

[Sarastro]

You speak of a 20-minute break in--was the engine recently rebuilt? If so, why wouldn't a camshaft problem be noticed?

I really doubt that you have a seriously worn lobe. That would be major damage, with noise and lots of metal in the oil. The lifter would be a mess, too. More likely you just didn't get the valves adjusted right. I suggest going through it again using the shop-manual procedure.

Or, I'd take Frank's advice and put a micrometer on the end of the pushrod. I think it would be easiest, in the long run, to take off the rocker assembly. Then set up the micrometer with a magnetic holder, turn the engine over by hand (remove the plugs to make it easier) and see what the lift is. It's a really simple procedure and it will answer the question once and for all.

 

[Stevenry]

Steve,

When the cam was out, it was really obvious! I found very little metal shaving in the sump.

I left the engine in the car. The apron and radiator and head had to come off, so while the head was off I was able to inspect and then lap the valves. The cost of the cam, lifters/tappets, push rods, and gaskets etc was probably around $500. I’m sure I saved a ton not having a shop do it. The apron wasn’t too difficult on a TR2 because the bumper supports are below it.

Steve

 

[DavidApp]

The distributer was the issue on the TR3B I was working on. The mechanical advance weights were lose and the springs were weak. If you turn the rotor clockwise it should spring back when you release it.
The engine would idle OK but as you revved it up it shook.
Try to get a magnetic base to hold the dial indicator.

David

 

[sp53]

My problem reminded me of the problems you posted David when you were working on your friend’s car. My symptoms are the same and I am still hoping it is the dissy movement.

I broke the car in with a 20 minute idle at 2K. This is the first time I have got the car out some more to get a good feel for the car. Mostly because I have a Top on it now; boy those Robins Tops-- should not leak what a contract.

I babied the car because the valve train sounded too noise. As I did drive it, I could feel the power loss and some sucking or starving from the engine. but figured I could work it out with tuning because I had leaking carbs, and timing, and dwell and you know the deal, probably.

I am starting see how a dial indicator would rule out the cam like Frank and Steve M. suggested plus take another look at lash setting. What put the light on for me, and how I could test stuff with a dial indicator was when Steve suggested removing the rocker assembly, and then looking at the height of the push rods.

From what I am seeing, I should be able to measure with a ruler the lack of lift in #1 intake. Today I will pull the plugs to see how rich it is running and remove the valve cover and stare at the car.

Steve

 

[CJD]

Hate to say it Steve, but it sounds like the cam may be bad. Have you drained the oil to look for metal? You can check the valve lift with a ruler, but if it shows with a ruler it is really gone.

 

[Stevenry]

With my two badly worn lobes, one exhaust and one intake, an the first and third cylinders, the car started and seemed to run fine, but started to rattle/knock between 3,000 and 3,500 rpm. With no load under 3,000 rpm, there was no noticeable problem. Because it seemed to run right, that’s why I was looking for maybe the exhaust banging against the transmission or something. Discovered the cam situation adjusting the valves after timing to make sure it wasn’t just pinging.

 

[sp53]

Well I measured with a ruler that an open valve is 1-5/8 above the head on outer edge at the top of a push rod. All mine are 1-5/8 except #2 intake which is 1-5/16 a difference of about 3/8. The picture of the cam lying on head is probably difficult to see, but effective to understand. What I am trying to demonstrates is the #2 intake and 3 # exhaust are both open at the same time. The picture shows how #3 exhausts is open and #2 intake is not open when # 2 should be open. #2 intake actually does not move, but about 1/16 WTF.

Anyways it is new cam time and I could use some suggestions. I kinda like the idea of a performance cam, but I hear stories that a performance cam will not let the engine idle down. I prefer a tr3 that would idle at 8K or 9K. I really do not like it when the engine idles at say 11K or 12K, so Stevery what does your engine idle at with the performance cam. Or is all this high idle stuff only for more serious racing cams. And I need any suggestions that would help me with my decision on which cam to get and anything else, anything.

Thanks Steve

 

[CJD]

Well, the car looks great!

I would check your oil for metal. If a lobe flattened you will have a lot of metal in the pan and filter.

 

[Stevenry]

Steve,

My old cam was hotter, and had a cool lope at idle, but I couldn’t get it to idle at less than 1,200 rpm, and it didn’t just shut off without slowly dropping the clutch in 4th. The new cam I got from British Parts Northwest is supposed to add low and midrange power, which is probably more appropriate to how I drive. Shuts off like it’s supposed to. I haven’t retuned the carbs yet because with the last of the nice weather, when I have time I drive the 20 miles or so to a nice golf course. It is idling slower than it did before, and I am fairly confident I can get it to idle smoothly in a normal range. I might tune the carbs this weekend, rain in the forecast, and can report.

I do have a high port TR4 head, 89 mm sleeves, and 4 to 1 header, so the car can take advantage of the increased flow the cam supposedly delivers. I have also found British Parts Northwest helpful over the phone. They directed my call to their “cam guy” regarding break in.

What part of Washington are you in? I’m in Olympia.

Steve

 

[sp53]

I have been chasing this problem ever since I got the motor running. This summer I mostly worked on my truck project, but did do whatever came to mind on the tr3, but again I never could get the sputter flutter problem out. In a way I will be glad if it is the cam because I found the problem, plus I am almost positive the cam is the problem what else could it be. I put together a different distributor with a spring set that returned with a click; it might have ran a little better, but the performance is wrong and the engine has a weird lifter nose. I am fairly certain the problem is the cam.

Some good news is the overall car seems fine, brakes, suspension, cooling, electrical and everything is clean and not rusty.

John, I drained the oil into a white garbage bag placed into an oil drain container and there was no obvious metal. I tried with a magnet to fish some metal out but no go. The metal is probably in the pan or pump screen or in the oil filter. Today I will pour the oil through a paint filter to find some particles.

Thanks for the information on your engine Steve. I will call the guys at BPNW for their data. I live in University Place which is next to Tacoma on the West side. Your car you said is a tr2 we do not see many of those around here. There was a guy down in Olympia selling a couple of tr3s some time back, and I was thinking about buying one, but the add has been off Craigslist for some time.

I guess I will start taking the engine apart this winter and see where that takes me. The bummer is I got the front end on the car to fit nice with a lot of pushing and pulling. I guess I could drop the pan and look up and see # 2 intake with a flashlight and then check the pan and screen for metal.

steve

 

[sp53]

Went down and dumped the oil from the filter into a painting filter and it was full of metal chunks. Anyways, I am not sure how much of the engine needs to come apart. I kinda do not want to pull the crank. I guess the rest needs to be cleaned. How about the oil gallery that goes down the side?

This is going to be a leaning procedure for me. The front seal leaked and now I can fix that, so I got that going for me----- must get the light right or I get a headache



steve

 

[CJD]

Well bummer.

If you have the later, full flow filter head, then 100% of the oil goes through the filter. In that case you are good leaving the crank in. The TR2 and very early TR3's used the "bypass filter", where only the oil bypassed to reduce the pressure goes through the filter. The TR2 would put all that metal right back into the oil galleries to the crank.

 

[Stevenry]

I did have to have my wife sit on a headlight to get a couple apron bolts started.

Steve

 

[sp53]

Thanks John I was hoping that was the case with the oil and the path it would take. I really appreciate you sharing your knowledge of mechanics. Last night I got thinking how could this happen and the thought hit me the valve could be stuck in the head and every time the lifter tried to open the valve the force of the stuck valve shaved the lifter. I guess the valve guide or the valve could be bent and perhaps the cam was weak also or both. Reminded me of the old Nietzsche line that” they that have a why can endure any How.

John what are your thoughts of a stuck valve? I remember many years ago in auto shop we had a manual spring compressor to remove valves. Anyways I am going to start taking the engine and body apart soon.

Steve I really appreciate your sense of humor and help must be all the rain here because I try to have one also. The Stephen King audible probably will not work for me because of all the voices in my head, saying WTF. No really, I listen to this oldie radio station out of Olympia on 101.9, but it is weak. Thanks you guys I need the help.

Steve