So true... I purchased a 1963 MGB 2 years ago from a guy I knew many years past. He was a mechanic at a Mercedes dealership when I was a Mercedes Factory Rep and visited the dealership on a monthly basis where he worked. I bought the car from him with no receipts and confident because we knew each other and he was a "professional" mechanic. I have spent 2 years and the same amount of money I paid for the car on parts in getting it right. Add to that 1000 hours. Me who has owned 30 Brit cars since 1964 and worked at an official BMC (MG included) dealership from 1968-1972). NEVER trust anyone when buying a car. Beware of the DPO, Dreaded Previous Owner. Though I am not a fan of the TR6, Excellent video as always...I have watched them all. , many thanks.
i just did a top end job on my 1974 TR6. I even rebuilt the rocker shaft since it was original and very worn out. The head was done by a quality machine shop. When I stared it up, it ran but very strangely. It was making a deep noise that wasn't there before. Then I found your video explaining what was going on. I'd adjusted the valves 3 times to make sure that weren't the problem, and they were all exactly .010", so I knew the problem I have. Now I have to wrestle with the machine shop for a proper set of springs and pull everything apart. Thank you for solving my problem. I only wish I didn't have to tear it back down again. Is it possible to replace the springs without pulling the head off? Excellent video, thank you for taking the time.
Hi, Its good you found the problem, I assume the spring are getting coil bound. You can remove the valve spring without taking the head off. It is done by putting and keeping air pressure in the cylinder via the spark plug hole. This is when the cylinder is on TDC on Compression. Then you can compress the valve spring and remove it. There are various tools to do this here is a link is to a cheap one , give you an idea of what you need. www.harborfreight.com/overhead-valve-spring-compressor-59343.html The air pressure stops the valve going into the Combustion chamber, You can use a long piece of string fed in to the plug hole with the piston on BDC and then turn the engine towards TDC compression till it holds the valves but the air is easier. (leave the end of the string hanging out the plug hole so you can reverse the engine and pull it out when finished.) If the machine shop has fitted valve seats, they may have set them to far into the combustion Chamber causing the problem with the spring length, just a thought. James
@@Dr-Doolincom Hello James. Thank you for getting back to me. The only answer can be coil bound springs. This morning, I called the machine shop and asked him what springs he used. He said he purchase the Moss Motors Spring kit. That is for a 1974. The older models '72 and older used a single spring, I think. He asked about the cam, and I assured him it was stock and not a high lift. Remember that this car ran fine before with the old springs, so that isn't it. The machine shop owner, very smart guy, now wants the head off so he can inspect the spring heights. That means I have to pull it off again and take it to him, an hour away. I don't mind much. After I saw your bent push rods, I ordered a stock set of them and a new head gasket. I placed a long straight edge over all the valves, and they are all the same height. I've removed valve springs using compressed air in the cylinders before. But this time we are doing the work at my friend's house, not in my shop, so we don't have a compressor. Mine is too big to move. Moss Motors sells just inner springs #831-037. I wonder if those inner springs are different than the ones in the full kit #831-038. When the springs come off, we will know what we're dealing with. We pull off the head this Thursday and take it up on Friday. I'll let you know how it goes. Many thanks, Ken
@@Dr-Doolincom Hi James, Correction; we took the head into the shop yesterday and they disassembled it and measured the springs. We previously measured the cam lift x 1.47= .365". Then they measured the inner coils, and they were fine. It would have taken another .200" to coil bind. We also checked the valve guides, and they are cast iron and installed correctly not blocking the intake ports. The valve job was professionally done, and it checked out perfect. At least we eliminated that fear. The other thing we noticed was that the rear 3 cylinders were wet on the exhaust ports. This points to the rear carburetor. All carb and ignition tuning were done previously to the head rebuild so that's not it. It ran well before. Now we are left with that rear carb causing trouble. It seems to be running rich, and it will be looked into. They are Stromberg's and have been carefully rebuilt and were running well for 3 months. However, there is something wrong and we will find it when we put the head back on. Waiting for gaskets and a new set of push rods to go with the rebuilt rocker shaft. The fun never ends. I will let you know what the Demon is when we find it.
So true... I purchased a 1963 MGB 2 years ago from a guy I knew many years past. He was a mechanic at a Mercedes
dealership when I was a Mercedes Factory Rep and visited the dealership on a monthly basis where he worked.
I bought the car from him with no receipts and confident because we knew each other and he was a "professional" mechanic.
I have spent 2 years and the same amount of money I paid for the car on parts in
getting it right. Add to that 1000 hours.
Me who has owned 30 Brit cars since 1964 and worked at an official BMC (MG included) dealership from 1968-1972).
NEVER trust anyone when buying a car. Beware of the DPO, Dreaded Previous Owner.
Though I am not a fan of the TR6, Excellent video as always...I have watched them all. , many thanks.
I always admire your analysis. Thank you for posting.
Glad to see you back. Great Video!
Very informative & interesting James, Thanks!
Could have been a disaster, you saved this customer…..Well done .
Nice to see you back
Great video Dr keep them coming
Great Video. Very Informative and interesting!
Great work
Brilliant content, thanks.
i just did a top end job on my 1974 TR6. I even rebuilt the rocker shaft since it was original and very worn out. The head was done by a quality machine shop. When I stared it up, it ran but very strangely. It was making a deep noise that wasn't there before. Then I found your video explaining what was going on. I'd adjusted the valves 3 times to make sure that weren't the problem, and they were all exactly .010", so I knew the problem I have. Now I have to wrestle with the machine shop for a proper set of springs and pull everything apart. Thank you for solving my problem. I only wish I didn't have to tear it back down again. Is it possible to replace the springs without pulling the head off? Excellent video, thank you for taking the time.
Hi, Its good you found the problem, I assume the spring are getting coil bound.
You can remove the valve spring without taking the head off. It is done by putting and keeping air pressure in the cylinder via the spark plug hole.
This is when the cylinder is on TDC on Compression. Then you can compress the valve spring and remove it. There are various tools to do this here is a link is to a cheap one , give you an idea of what you need.
www.harborfreight.com/overhead-valve-spring-compressor-59343.html
The air pressure stops the valve going into the Combustion chamber, You can use a long piece of string fed in to the plug hole with the piston on BDC and then turn the engine towards TDC compression till it holds the valves but the air is easier. (leave the end of the string hanging out the plug hole so you can reverse the engine and pull it out when finished.)
If the machine shop has fitted valve seats, they may have set them to far into the combustion Chamber causing the problem with the spring length, just a thought.
James
@@Dr-Doolincom Hello James. Thank you for getting back to me. The only answer can be coil bound springs. This morning, I called the machine shop and asked him what springs he used. He said he purchase the Moss Motors Spring kit. That is for a 1974. The older models '72 and older used a single spring, I think. He asked about the cam, and I assured him it was stock and not a high lift. Remember that this car ran fine before with the old springs, so that isn't it. The machine shop owner, very smart guy, now wants the head off so he can inspect the spring heights. That means I have to pull it off again and take it to him, an hour away. I don't mind much. After I saw your bent push rods, I ordered a stock set of them and a new head gasket.
I placed a long straight edge over all the valves, and they are all the same height. I've removed valve springs using compressed air in the cylinders before. But this time we are doing the work at my friend's house, not in my shop, so we don't have a compressor. Mine is too big to move. Moss Motors sells just inner springs #831-037. I wonder if those inner springs are different than the ones in the full kit #831-038. When the springs come off, we will know what we're dealing with. We pull off the head this Thursday and take it up on Friday. I'll let you know how it goes. Many thanks, Ken
@@Dr-Doolincom Hi James, Correction; we took the head into the shop yesterday and they disassembled it and measured the springs. We previously measured the cam lift x 1.47= .365". Then they measured the inner coils, and they were fine. It would have taken another .200" to coil bind. We also checked the valve guides, and they are cast iron and installed correctly not blocking the intake ports. The valve job was professionally done, and it checked out perfect. At least we eliminated that fear. The other thing we noticed was that the rear 3 cylinders were wet on the exhaust ports. This points to the rear carburetor. All carb and ignition tuning were done previously to the head rebuild so that's not it. It ran well before. Now we are left with that rear carb causing trouble. It seems to be running rich, and it will be looked into. They are Stromberg's and have been carefully rebuilt and were running well for 3 months. However, there is something wrong and we will find it when we put the head back on. Waiting for gaskets and a new set of push rods to go with the rebuilt rocker shaft. The fun never ends. I will let you know what the Demon is when we find it.
That was a great video!! Thank you!
In the late '60s I had a pushrod break on a Ford Falcon whilst going 55 mph. Guess that Ford product couldn't handle such high speeds.
What a mess that was!