|This is a place that looks like it's dealt with old iron.|
|The building is at least one hundred years old|
and used to be a blacksmith's shop.
|There are usually several vintage machines waiting to be worked on.|
|All photos from their website.|
The shop is well respected in the community.
I was at such a loss that I decided that I had to spend some money and get a professional's opinion. I had totally run out of ideas. There was a nearby shop that inspired some confidence. I dropped in to discuss my problem with the shop owner and he told me to bring the car in. So I fired up the Riv and clattered my way down the road.
The owner asked if I was in a hurry to get the car back. I told them that they could take their time. He agreed to take a look at it in between other jobs, in order to save me a little money. That sounded good to me.
I made it a habit to occasionally stop by the shop after work to see what progress has been made.
They told me that they haven't found anything, so a top end tear down was needed. They removed the rocker shaft and the first issue made itself known. They showed me that the valves are not all at the same height, some are standing taller than the others. It seems that my random machine shop ground the valve seats excessively, so that some were sunk pretty deep into the head. They should have then trimmed the valve ends to keep everything even. While this is a workman like approach to a non performance rebuild, that would have worked okay. But this could lead to some problems. The shortened valves would not have opened up as much, and they would be shrouded by the valve seat, reducing air flow. Still, good enough for a grocery getter.
The best repair would have been to replace the valve seats with hardened inserts and maintain the original valve position and operation. This would have cost a lot more, however.
Could they fix the problem?
The cure would be to dissemble the heads, remove the valves and machine the tips of the valves to shorten them.
But would this uneven valve situation have caused the noise? Probably not. So they pulled the heads and got quite a surprise.
After pulling the heads they found that some of the valves were actually hitting the piston tops. That would definitely make a tapping sound! But how could this have happened?
During a rebuild the head is usually surfaced to make sure that it is flat and will seal properly. Care has to be taken so that adequate valve clearance is maintained. Sometimes, the valve reliefs cast into the piston crown may have to be machined a little deeper for clearance. Sometimes a thicker head gasket might be called for. If a thicker head gasket is not available sometimes two gaskets are used. Now things are getting a little Mickey Mouse! Still this was a common work around back when these engines were run of the mill.
That is what made that tapping sound.
What? That machine shop just ground down the valve seats and machined too much off the surface of the head. Now, a couple of the valves may have gotten a little bit bent. Luckily the mechanic didn't think that there had been any damage done to the connecting rod or bearing
These heads could be saved with a lot of work but it would be better, cheaper and easier to find another set. I just have to provide them another set of heads and they can do the valve job and reassembly. I just spent 500.00 for them to find the problem and now the engine is in pieces! Time to regroup and stop the bleeding.
The shame. I drove the car down to the shop, but now I'm having it towed back to my house!
|photo source: engine basics .com|
Typical OHV set up.
photo source: grumpy's performance .com
This is what valve seats look like.
Now I needed to find another set of heads.
Where else to go but Pick and Pull?
In the early 1990's There was still quite a few 1960's cars available in the yards
I found a fairly clean, almost complete motor in a wrecked '66 Riviera. I noticed that the wheel wells were painted white inside. This led me to believe that the car once had nice wheels on it. Probably not too long ago.
I looked at the block and found an engine rebuilder's plate above the oil pan. It belonged to a shop located in Oakland,
It was neat and clean under the rocker covers, a very good sign.
I decided to buy the whole engine, it was on sale anyway. It's the cheapest route. Unfortunately the the distributor and carb were already gone. No discount for that, since the motor was only 300 bucks.
This is the smartest way, buy the complete motor. Just be sure to take all the nuts, bolts, brackets and accessories that are included in the purchase price.
I was pretty sure that this motor was going to be a good one. After seeing that rebuilder's plate and how clean the engine was inside the the rocker covers. Another clue were the painted wheel wells, I'd bet that some body had a nice set of wheels on the Riv before it was crunched. And it was crunched. The left rear quarter panel and rear bumper were pushed in at least a foot.
That meant that the car was scrapped because of the collision damage, not because the motor or tranny were shot. As long as the accident didn't damage the power train it's good to go. If you see a straight old car with weathered, worn out paint, and a filthy tattered interior, you can bet that the motor is as worn as the body.
That was what was meant by mistake number two.
Oftentimes you can find a good deal on a good used engine. It is faster, easier and cheaper if you can swap in a complete wrecking yard motor than to rebuild the original unit. I had invested quite a bit of money in the rebuilding of the original motor. Unfortunately I had not done my due diligence in my first choice of the machine shop to rebuild the heads. I then did not check the clearances of the valve train before installing the motor in the car and firing it up.
Luckily, that junkyard motor turned out to be a real jewel.
Despite all these mistakes and all the unnecessary money spent, I still finally ended up with a strong running Riviera that gave me many years of service. An education never comes without a cost.