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A little ignition help needed

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Replacing the timing chain and related parts is a relatively minor job, compared to many others. Be happy! Look how much all of the BFC members are learning from this thread. If I could snag a company trip out there I would be turning wrenches with you.

Phil

You could always exchange the carb and the muffler. Ducks real quick.
 
Thanks Ernie. I too hope it is just the tensioner. I'll be sure to post the results for everyone's reading pleasure :smile:
Bob
 
Thanks to you too Phil !! I do beleive the timing chain cover is next to come off. Looks like I can pick up a new chain, tensioner, gasket and seal fairley reasonably if needed.
Have a great day!
Bob
 
Not pretty.....but not too bad, either.
DPO MADE a Woodruff key. You can see the grind marks. Tapered, too short in length, worked into the crank pulley hub and let go of the crank timing gear.
Pounded the living poo out of the shims.
Parts ordered.
Don got to see how to remove the crank bolt with the starter!
Dave
 
WOW!! is all I can say!! Don, Dave.... I can not thank you guys enough for your help with my LBC.
Today, we removed the timing chain cover and found that the crank shaft key that holds the pulley and timing chain sprocket in alignment on the crank shaft looked like it was home made, worn out and not fitting correctly at all. What was happening was when the engine was turning over, the timing gear was not spinning with the crank. There was enough friction to drive the cam and valves but the correct timing would never happen as the gear was slipping on the shaft. Also the 3 spacers behind the sprocket were so worn out that one had a big chunk missing out of it.
Dave, your ideas on how to do things the easy and right way are extreamly helpfull especially using the breaker bar and engine to break the pulley nut loose.... What a piece of cake! I have the new replacement parts ordered and they should be here sometime next week.

I also want to thank everyone else who contributied to this thread. Your ideas and suggestions are very helpfull. I'll be back and let you all know what happens when and if I get this back together. Thanks again EVERYONE!!!

Bob C.
 
Get the book out and familiarize yourself with re-assembly, then, when parts arrive and you look at them, you may wonder how the parts go in, even with the manual....happens.....then call, I and maybe Don will come out, help you get it together, and get it lit!
Still wondering about the arc-weld spot on the crank bolt......
 
Dave the weld spot was not much. I took a small chisle and tapped it with a hammer lightly and it poped right off. Kind of like it was a piece of stray slag.
Phil, sorry about the lack of photos. Got all caught up in the excitement of finding the problem. Like TOC said, the key looked very much home made. Grinding marks, not symetrical and groved from not fitting in the keyway properly allowing the timing gear to slip around on the crank shaft. Tried to take pics of the key after we got it out, but it is too small to get close enough to take a clear picture.
 
bnw said:
RANDALL!!!!!
Click to expand...

Yeah, when I said "Houston, we have a problem" and asked for the bolt size, I knew. You don't A)zero compression, B) pressure out the carb, nor C) vacuum at the plugs unless we have a serious cam timing issue.

Once you get the data, the diagnosis is fairly easy.

Sometimes you want to line DPO's up and slap them silly.
 
rcufley said:
Dave the weld spot was not much. I took a small chisle and tapped it with a hammer lightly and it poped right off. Kind of like it was a piece of stray slag.
Phil, sorry about the lack of photos. Got all caught up in the excitement of finding the problem. Like TOC said, the key looked very much home made. Grinding marks, not symetrical and groved from not fitting in the keyway properly allowing the timing gear to slip around on the crank shaft. Tried to take pics of the key after we got it out, but it is too small to get close enough to take a clear picture.
Click to expand...

Yeah, but the slag shouldn't have been there. No reason I can think of unless someone tried to weld up a damaged bold, but then that's have ground it off anyway. Odd.
Dave
 
Check the fit of the sprocket on the crankshaft when you put it back together. Most likely it's OK, but if the crank is worn undersize enough so you can feel any play at all, then you may want to use Loctite RC648 or similar to improve the fit. Otherwise it may continue to work back and forth against the key, and eventually waddle it out again.

Also make sure the center bolt is pulling down against the sprocket (clamping it firmly against the shims). I don't know what a Spit 1500 looks like there, but on my TR3A I managed to have the crank bolt pulling up against the end of the crank instead of the pulley hub, sprocket and shims. Didn't notice until about 30k miles later, when it got loose enough to start making noise.
 
TR3driver said:
Check the fit of the sprocket on the crankshaft when you put it back together. Most likely it's OK, but if the crank is worn undersize enough so you can feel any play at all, then you may want to use Loctite RC648 or similar to improve the fit. Otherwise it may continue to work back and forth against the key, and eventually waddle it out again.

Also make sure the center bolt is pulling down against the sprocket (clamping it firmly against the shims). I don't know what a Spit 1500 looks like there, but on my TR3A I managed to have the crank bolt pulling up against the end of the crank instead of the pulley hub, sprocket and shims. Didn't notice until about 30k miles later, when it got loose enough to start making noise.
Click to expand...

The key is really poorly made. If it was new, I'd say PRC. I didn't measure the length of the crank slot, but let's say 1.25". This key is 1.0" or so, fatter at one end, ground down with a bench grinder. The crank gear looks okay inside, the crank sort of feels okay, lock-tite is what I'd use, but gotta get the new parts.
 
So, after giving this a considerable amount of thought, I have decided, as long as I have taken the engine this far apart, I probably should go ahead and take the head off and have a valve job done. Also, as long as I have gotten this far I should have the head shaved approximatly .030" and have the cam changed out. This will take another week or so to get all this stuff done. One of the re-assembly concerns I have is getting the distributer placed back in the correct position.
 
And so it begins.
That kind of thinking will lead you down the path of ....
 
Don, you think I should not do the head and cam thing and just fix the timing gear problem? I was thinking that a valve job would not hurt as long as I have the engine this far apart. Then if the head off, might as well have it shaved a little. And as long as the head is off, might as well pull the cam and have it worked to get the little engine sounding like it has a little umph to it. Do you think I am going down a bad road? I know doing the cam and head stuff would add about another $500 or so. But, maybe I could get a Sr. Citizen discount.
:smile: I am a little afraid of pulling the cam and getting it and the distributer drive gear back correctly so the timing will be correct.
Bob
 
It sounds like you only had a sprocket/key problem. If it were me, I'd carefully put that back together, probably add a new tensioner, and maybe a new timing chain because of whatever stress and distortion may have occurred. I'd make sure everything is properly aligned, and may add a speedy sleeve with the new timing cover seal if there's any sign of wear or leaking, and carefully seal the cover with a new gasket of course.

You're planning that much anyway I believe.

Not sure I'd go down the slope of removing the head. These cars are fun, and you'll have time for that if you need to go that route. Removing the head could cause you to have head gasket issues, issues with block studs, and on and on--when nothing may have been wrong. Also, while you had suspected some kind of valve problem, there really isn't any evidence of valve trouble if I recall correctly.

BTW, if you do pull the head, etc., don't worry about getting the timing back correctly. That will be fairly easy. You'll want a good manual and some help from the guys around here, but once you've got the chain and sprockets properly aligned, it's an exercise of dropping the distributor gear in correctly so that at TDC on the compression stroke cylinder no. 1 is ready to fire. The mistake I last made was forgetting that TDC doesn't mean you're necessarily on the compression stroke.

Good Luck and have fun with it.
 
Bob,You may want to assemble your new timing parts and do a compression check before you lock everything down and install cover.Then you can make a decision on head/valves condition.
Have Fun
Tom
 
Don, Tom, KVH.. Thanks for the feedback. I will take your advise and not mess with the head or cam. I have already removed half of the head bolts but not the water pump or manifold. So I will re-install and torque the head bolts and just put the timing kit together when it arrives. Thanks again for your advise, it is extreamly valuable to me and I hope others on this forum!!!
 
The problem is not your current plan, but once everything is apart for the cam and head change, than the plan may increase in scope. If this is your final goal I would only change the cam and lifters and save the head for a later time. If you reassemble to stock condition with the existing cam timed properly you may have an increase in performance and you can check the compression and see if you will need an entire engine rebuild to handle the increase in power from any modifications. The stock English cams were always hotter than stock American equivalents, maybe 3/4 race. Driving on the street you may never get on the curve of the cam if you install a hotter one.
 
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