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Failure on Initial Engine Start After Rebuild

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I have to say, as a new forum member and aspiring Healey owner, the help and advice gadwhite has received in this thread are exceptional. I am learning a lot just by following along, and am glad to have found such a resource. Bravo!
 
Good news. Sorry it’s been a while since I posted. Got the engine to fire, it wouldn’t stay running but when I checked the carbs found I hadn’t put the oil in them. Topped up to the line in the damper tube and the engine starts and idles nicely. I don’t even need to choke it. I want to thank everyone who helped me and most of all for their patience. This is the first engine I have put together and if it hadn’t been for the builder setting the timing wrong on my short block it would have gone smoothly. Thank you thank you thank you . I will post a short video soon
 
Congratulations!

I have to say though that not having to "choke it" is not necessarily a good thing IMO.

Danny
 
Congratulations, it's always gratifying to hear a newly rebuilt engine start up and run. Now, on to the more subtle tuning tweaks :encouragement:!
 
Danny I actually agree and probably my idle is a little high, so I think after I tune the carbs I may have to choke. I was just so happy to hear the new engine fire and run so smoothly. I have a bit of work to do on the cooling system and the exhaust then I'll do a proper start and tune the carbs etc. Then i'll post a video to close out the thread.
 
Glad to see your engine up and running after addressing the mechanical timing issue, with hopefully only electrical timing and carb tuning remaining.

(Not on Facebook, nor never will be, so can't see your video)
 
Struggling with the same thing. I've taken the timing cover off and everything lines up per the factory manual and the helpfully provided photos.
I'd figured this TDC was the same TDC used to adjust the valves and the ignition (ie the compression stroke). However, when I rotate the engine clockwise from this position the intake opens, meaning the cam thinks its at the TDC of the exhaust/intake stroke.
Is this correct? My engine builder is real cheap but he has a bad case of ADD so everything he does is suspect.
 
Are both valves closed? There is only one TDC ON COMPRESSION STROKE for the #1 ( or any other) cylinder. If you rotate the engine in direction of normal rotationy put your thumb over the spark plug hole and SLOWLY turn the engine with the crank nut, not the starter. If you feel compression against your thumb as you approach TDC you are at the correct TDC. If no compression you need to keep turning until you get compression. Sorry if I'm being too basic perhaps I misunderstand what you are asking.
 
I'm starting from scratch. I've completely releaved all the adjuster and all the valves are closed. With the engine at a TDC per the manual I adjust both valves for #1 to .012 per the plaque on the valve cover. As soon as I start to move the engine the intake valve starts to open. By the time I've gone all the way round the valve lash like 3/8".

If I start with the piston at the other TDC (dimple on the cam gear at the bottom) I can adjust the valves to .012 and follow the valve opening and closing thru the whole cycle fine. Compressing is good.

Before I put the whole thing together (again) I just want to make sure that piston TDC for compression is indeed with the dimple on the valve gear at BDC and pistonTDC for exhaust/intake is with the dimple at TDC. My head is starting to hurt!

Don't worry about being too basic - when I started this project I thought I knew what I was doing. I was wrong.
 
I'm starting from scratch. I've completely releaved all the adjuster and all the valves are closed. With the engine at a TDC per the manual I adjust both valves for #1 to .012 per the plaque on the valve cover. As soon as I start to move the engine the intake valve starts to open. By the time I've gone all the way round the valve lash like 3/8".​
Click to expand...

If you are on TDC of the compression stroke, the intake valve will not open as soon as you turn the engine because that would be the power stroke and the valves will remain closed as the burning of the charge pushes the piston down - sounds like you are TDC on the intake stroke, however you should not set valve clearance at TDC on intake stroke because the vale should already be partly opened - depending on the cam the intake will start to open about 5* or so before TDC.

The dimple on the cam sprocket will be at the top and the dimple will be at the bottom of the crank sprocket when you are at TDC on the compression stroke. I personally prefer to count the chain links between the dimples - since the links straddle the dimples,
looking at the from of the engine you should have 13 links on the right side and 16 links on the left side between the links that straddle the dimples. However you get there the pictures earlier tin this thread are what you want to achieve.

Once you have confirmed the correct number of links, then you can adjust the valves and the valve adjustment does not have anything to do with the TDC. I have attached a scan of the small card I carry in my wallet all the time. It is the best way I have found to adjust valves with the minimum turning of the engine - eg, when valve #12 is fully open adjust valve #1, when valve #6 is fully open adjust valve #7, etc. (counting valve from the front so cylinder #1 exhaust valve is valve #1).
Dave
valve ajust sequence_20180504_0002.jpg
 
"The dimple on the cam sprocket will be at the top and the dimple will be at the bottom of the crank sprocket when you are at TDC on the compression stroke. I personally prefer to count the chain links betweenthe dimples - since the links straddle the dimples,"

This is my problem. With the dimple at the top the valves behave like it's TDC for the intake stroke. It's like the cam is upside-down on the gear. If I could rotate either the gear or the cam 180 without moving the other it would be fine. They're both keyed so I don't think this is possible to put them together wrong. The cam was sent off by my machinist to someone else - I don't actually know what I got back. It was supposed to be mine reground. I did all the assembly so anything is possible

I too did the counting and the number.

I also counted the links (using the photo on the factory manual) and got the same count you use.
 
Hmmmm. Just starting thinking about your chart and I think I see what I've been doing wrong. I use this method tomorrow and see what happens
thx
 
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