Noise like Steam locomotive?
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Three Wheeling
Joined: Feb 2015
Posts: 87
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Hi
In the murky past, I have seen exhaust valves so badly burnt they were almost D shaped. While I don't expect yours would be that worn the valves and seats should be checked for leaks and pitting.
It was always drummed into me to have those valves perfectly mated to the seating. I don't personally believe a new valve in a new seating would be as gas tight as one that was lapped in.
In the murky past, I have seen exhaust valves so badly burnt they were almost D shaped. While I don't expect yours would be that worn the valves and seats should be checked for leaks and pitting.
It was always drummed into me to have those valves perfectly mated to the seating. I don't personally believe a new valve in a new seating would be as gas tight as one that was lapped in.
I could never achieve that quality but it's something to aim for compression leakage wise..
Last edited by lrguy46; Aug 4, 2015 at 09:54 AM.
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Three Wheeling
Joined: Feb 2015
Posts: 87
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The reason I'm so keen on this is that I have an engine in the shop and it is my first time to do so. I had the bottom end checked and cleaned, cylinders honed, the crank has been turned and the main bearings and rod bearings have been ordered, and the heads have been pressure checked and planed ever so slightly. The whole project is awaiting arrival of my seriously late new camshaft. But I don't remember asking that anything be done with the valves. I just didn't think about that when I dropped it off... I suppose I should give them a call and, while we wait for the cam, get the valves seated??? Sorry to interject on this thread but the valve issue just hit my radar screen and has me worried.
It's not just the valve seating to check... it's also the state of the valve guides and any signs of excessive wear. Obviously you will change the oil seal and, if neither checked, you will see familiar puffs of blue smoke from the exhaust on the overrun. Old BMW's are famous for this!
Also, the valve springs... after 100,000 miles they have taken a pounding and if you put an old one up against a new one you will see the old one is about 1/8" shorter. As a result of replacing with a new and firmer spring you will find the engine will rev better and you won't get valve bounce (sometimes called flutter) until much later.
Some sportier engines I've worked on had double valve springs for higher pressure and higher revs but the rest of the valve gear has to be up to the extra load... I doubt the Rover is a candidate even if a conversion kit could be found!
Also, check the oil ways in the rocker shaft are clear...
Camel Trophy
Joined: Nov 2012
Posts: 3,717
Likes: 248
From: Longview, Texas
A PS to my prior post...
It's not just the valve seating to check... it's also the state of the valve guides and any signs of excessive wear. Obviously you will change the oil seal and, if neither checked, you will see familiar puffs of blue smoke from the exhaust on the overrun. Old BMW's are famous for this!
Also, the valve springs... after 100,000 miles they have taken a pounding and if you put an old one up against a new one you will see the old one is about 1/8" shorter. As a result of replacing with a new and firmer spring you will find the engine will rev better and you won't get valve bounce (sometimes called flutter) until much later.
Some sportier engines I've worked on had double valve springs for higher pressure and higher revs but the rest of the valve gear has to be up to the extra load... I doubt the Rover is a candidate even if a conversion kit could be found!
Also, check the oil ways in the rocker shaft are clear...
It's not just the valve seating to check... it's also the state of the valve guides and any signs of excessive wear. Obviously you will change the oil seal and, if neither checked, you will see familiar puffs of blue smoke from the exhaust on the overrun. Old BMW's are famous for this!
Also, the valve springs... after 100,000 miles they have taken a pounding and if you put an old one up against a new one you will see the old one is about 1/8" shorter. As a result of replacing with a new and firmer spring you will find the engine will rev better and you won't get valve bounce (sometimes called flutter) until much later.
Some sportier engines I've worked on had double valve springs for higher pressure and higher revs but the rest of the valve gear has to be up to the extra load... I doubt the Rover is a candidate even if a conversion kit could be found!
Also, check the oil ways in the rocker shaft are clear...
Thanks for the tips. As I said... first time for me. I've just slapped head gaskets on and used some brake cleaner to cleans things up before, and I want to do this one right.
I called the engine shop and the owner, who has been doing engines for 50 years, kindly told me that he'd already seen to the valves and passages and that the engine looks like it just came off an assembly line. Just waiting on the camshaft. Crower is so slow.
Best,
Charlie V
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Three Wheeling
Joined: Feb 2015
Posts: 87
Likes: 3
Geoff,
Thanks for the tips. As I said... first time for me. I've just slapped head gaskets on and used some brake cleaner to cleans things up before, and I want to do this one right.
I called the engine shop and the owner, who has been doing engines for 50 years, kindly told me that he'd already seen to the valves and passages and that the engine looks like it just came off an assembly line. Just waiting on the camshaft. Crower is so slow.
Best,
Charlie V
Thanks for the tips. As I said... first time for me. I've just slapped head gaskets on and used some brake cleaner to cleans things up before, and I want to do this one right.
I called the engine shop and the owner, who has been doing engines for 50 years, kindly told me that he'd already seen to the valves and passages and that the engine looks like it just came off an assembly line. Just waiting on the camshaft. Crower is so slow.
Best,
Charlie V
That's good... you can sleep easy now!
Ironically I found this YouTube on how to grind valves by an old timer but he was taught wrong! You must not spin the valve... you have to reciprocate back and forth to get an even finish... that's why they make devices specifically to do that and the age old wooden dowel is twisted back and forth between the palms of your hands to achieve the same effect.
Pro Wrench
Joined: May 2010
Posts: 1,918
Likes: 86
From: St Louis MO
VersaChem 13209 - Valve Grinding Compound | O'Reilly Auto Parts
Just had to post since I work there...
Just had to post since I work there...
Thread Starter
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Three Wheeling
Joined: Feb 2015
Posts: 87
Likes: 3
VersaChem 13209 - Valve Grinding Compound | O'Reilly Auto Parts
Just had to post since I work there...
Just had to post since I work there...
Do you have a spray similar to this - Berkebile Oil 2 + 2 B101 Instant Gum Cutter - 13 oz. - that I tried to buy but can't get it imported... the guy in the video was using it to dissolve carbon.
Pro Wrench
Joined: May 2010
Posts: 1,918
Likes: 86
From: St Louis MO
If I had to venture a guess, I would think that Sea Foam Spray - Sea Foam Sales Company would be the most similar product? I know for a fact that Deep Creep - Sea Foam Sales Company removes carbon as there was a Ford TSB that recommended it for the Triton engines when removing spark plugs. It is extremely common for those plugs to break off in the cylinder due to carbon build up. I used it on a neighbor's Excursion when changing plugs and none broke. The ceramic on the plugs had liquified carbon on it after we removed them. It wiped off with a finger.
I wouldn't recommend it for anything internal on an engine though.
The Deep Creep has replaced PB Blaster as my penetrant spray.
I wouldn't recommend it for anything internal on an engine though.
The Deep Creep has replaced PB Blaster as my penetrant spray.