Bringing My '79 Bonneville Special Back to Life

L.A.B.

VIP MEMBER
Joined
Nov 20, 2004
Messages
15,551
Country flag
Tulsaalva said:
Meriden, in the meantime, had developed a three chambered pump which was intended to produce higher oil pressure. An attempt was made to retro-fit all the bikes we sold with the new pump but I don't know if our Bonny got the upgrade or not. I soon will.
Al,

Thanks for the interesting Meriden anecdote!

The only upgrade the factory made to the oil pump that I'm aware of, was a new (71-7317) four valve pump introduced for 1980 that had two extra exhaust ball valves?

A small amount of metal has to be removed from the inside of the timing cover in order to fit the four valve pump in place of the original two valve pump.

http://www.britishcycle.com/Products/tr ... _pumps.htm
 
Joined
Sep 3, 2007
Messages
169
L.A.B. said:
Tulsaalva said:
Meriden, in the meantime, had developed a three chambered pump which was intended to produce higher oil pressure. An attempt was made to retro-fit all the bikes we sold with the new pump but I don't know if our Bonny got the upgrade or not. I soon will.
Al,

Thanks for the interesting Meriden anecdote!

The only upgrade the factory made to the oil pump that I'm aware of, was a new (71-7317) four valve pump introduced for 1980 that had two extra exhaust ball valves?

A small amount of metal has to be removed from the inside of the timing cover in order to fit the four valve pump in place of the original two valve pump.

http://www.britishcycle.com/Products/tr ... _pumps.htm
As usual Les, I believe you're right and your encyclopedic knowledge comes to the rescue of my thirty year old memory. :D After looking at the drawings of pump #71-7317, I believe it is the replacement pump that was used. I can't be sure, of course. It is possible there was a discarded three-valve design between the two but I doubt it. My guess is that my memory was wrong. I do remember that David had to remove material from the timing cover in order to fit the new pump.

LaNelle carries the new pump: $195.00! Ouch! Now I need to go see if I need one.

Thank you!

Al
 
Joined
Dec 13, 2008
Messages
5
L.A.B. said:
Tulsaalva said:
Meriden, in the meantime, had developed a three chambered pump which was intended to produce higher oil pressure. An attempt was made to retro-fit all the bikes we sold with the new pump but I don't know if our Bonny got the upgrade or not. I soon will.
Al,

Thanks for the interesting Meriden anecdote!

The only upgrade the factory made to the oil pump that I'm aware of, was a new (71-7317) four valve pump introduced for 1980 that had two extra exhaust ball valves?

A small amount of metal has to be removed from the inside of the timing cover in order to fit the four valve pump in place of the original two valve pump.

http://www.britishcycle.com/Products/tr ... _pumps.htm
The oil pump is removed and appears (to me) to be the original two-valve unit. There is no part number stamped on it. (I'm spoiled by Porsche in this regard.) From the looks of the diagram and from my memory of the four-valve units we used in Germany, the two bolts on the bottom of the newer unit enter the pump at an angle. The ones on my pump are in straight alignment, looking much like British Cycle's diagram of the original unit. Seventeen took some pictures of our pump but was unable to upload them and had to leave for an important engagement... a friend's birthday party. We'll try again when he gets home.

I found metal particles in the oil which seem to be aluminum, since a magnet does not attract them. Also, there is no sign of a modification on the inside of the cover.

My guess is that our Bonny missed the upgrade for the usual reason. "Use this last one on a customer's bike. We'll fix Al's later." "Later" never came because I sold the bike and my shares in the company and returned to Oklahoma. Two years later I got the bike back along with a set of pistons and a lot of other parts, (no oil pump) which the bike needed. By that time, our service manager in Germany had followed me to Tulsa and was working in a bike shop here. He fixed the bike then but apparently forgot that the bike never got the oil pump upgrade. That's my guess, anyway.

The bike was placed in storage then (about 1983) where it stayed until last year when we started bringing it back to life.

Al
 

L.A.B.

VIP MEMBER
Joined
Nov 20, 2004
Messages
15,551
Country flag
The 4 valve pump is a desirable upgrade, but as far as I know, it doesn't supply any more oil than the 2 valve one?

Literally thousands of those 2V pumps have been fitted to Triumphs over a 40 year period since the first Speed Twins were made in 1938, and they are an ingeniously simple and reliable plunger pump that only requires a single one-way valve on the exhaust side of each plunger (one for feed and one for scavenge) in order to work, however the weakness of the design is that it only needs a very small piece of dirt or swarf to become trapped under the ball valve to completely stop the pump working and extra care is always needed when cleaning the feed and scavenge strainers to ensure that no particles of dirt or swarf are allowed to remain that could possibly be dislodged a find their way into the pump. With two exhaust valves "in series", if one valve should become disabled by dirt trapped under the ball seating then the pump won't stop working.
The best modification that can be made in my opinion is to fit a paper element oil filter. Either a spin-on cartridge type that can be fitted into the reservoir return pipe, or a "Charlies" oil strainer conversion, that replaces the gauze strainer inside the frame oil reservoir with a paper element filter. There is also a spin-on filter kit that can be fitted on the supply side of the pump, although this setup requires modifications to be made to the timing cover.

This is the Charlies style filter I have fitted to my T140V with its 2V pump.



Most of these kits use a B25 filter. This one I have uses a slightly larger filter that I believe comes from a Mercedes car?
 
Joined
Sep 3, 2007
Messages
169
I'm sure the filter is a good idea, Les, judging from the debris I found in the oil. Cleanliness is always good in any engine. Where is it available?

British Cycle writes glowing of their 70-9421/A Morgo Rotary Triumph Unit oil pump kit. They write of better reliability, more oil flow, and steady flow as opposed to the pulsing flow with the plunger type. What do you think of these?

Al
 

L.A.B.

VIP MEMBER
Joined
Nov 20, 2004
Messages
15,551
Country flag
Tulsaalva said:
Where is it available?
I'd try your normal Triumph parts supplier (LaNelle?) first? As I've seen them offered for sale by USA parts suppliers, if you can't get one, then a lot of UK Triumph parts suppliers sell them. Let us know if you have trouble finding one in the US.

Tulsaalva said:
British Cycle writes glowing of their 70-9421/A Morgo Rotary Triumph Unit oil pump kit. They write of better reliability, more oil flow, and steady flow as opposed to the pulsing flow with the plunger type. What do you think of these?
I've read a number of mixed opinions about Morgo rotary pumps, some opinions are that they're simply unnecessary for road use and supply too much oil, the standard oil pressure relief valve certainly has to be modified to use one, but I haven't used one myself so I can't speak from any direct experience.
Personally I think I'd be more inclined to go for the Morgo plunger type if I intended to upgrade the oil circulation....which I'm not! http://www.morgo.co.uk/plunger.html
 
Joined
Sep 3, 2007
Messages
169
This morning I did the test described in the workshop manual. The pump failed. The ball on the larger-diameter side is not sealing.

I decided to try and fix the pump using the method we first used in Germany and described in the workshop manual (using a punch to smartly hit the ball to form a seat in the brass body). I'm embarrassed to say that I could only remove the square bolt on the small side. The bolt on the large side is so tight that the wrench rounded the corners.

I inspected the seat on the small side. Even though it seemed to be sealing, the seat is not evenly formed around the hole. I have declared the oil pump to be trash and will order a new one from LaNelle on Tuesday. (She doesn't open on Monday.)

In the meantime the bike has another challenge that may have contributed to the breakdown by lowering the oil level in the primary case. There is a crack in the aluminum where the primary chain adjuster threads into the primary case. It results in a drop of oil falling about every half-hour. I've been told by some blokes at LaNelle's that it's not an "unheard-of" problem. They referred me to a fellow whom they say is an artist with a Tig welder and can fix it "better than new." I like "better than new!"

Next, I'll learn whether I only need rings or pistons as well. Would anyone like to offer an opinion? Stock Triumph or after-market? Keep in mind that "better than new" is preferred. :)

I still need to learn where the aluminum chips in the oil came from and address that as well.

It looks like the "School of Hard Knocks" tuition has been increased by several hundred dollars. I don't like it but I refuse to cut corners on rebuilding a Bonneville. Every day we have fewer of them.

Thanks, Y'all!

Al
 

L.A.B.

VIP MEMBER
Joined
Nov 20, 2004
Messages
15,551
Country flag
Tulsaalva said:
The bolt on the large side is so tight that the wrench rounded the corners.
They are often very tight. The "large side" of the pump is the scavenge side.


Tulsaalva said:
In the meantime the bike has another challenge that may have contributed to the breakdown by lowering the oil level in the primary case.
I wouldn't have considered that to be a serious oil leak (not by Brit bike standards anyway) and it is doubtful that an occasional drip of oil from the primary case would have contributed to any engine damage, unless the level of oil in the frame reservoir had been allowed to drop to a dangerously low level as a result?



Tulsaalva said:
Next, I'll learn whether I only need rings or pistons as well. Would anyone like to offer an opinion? Stock Triumph or after-market? Keep in mind that "better than new" is preferred.
I'd still opt for standard replacement Hepolite/AP/Federal Mogul (or whatever else they may be calling themselves this week?) pistons and rings, no doubt other choices are available on your side of the pond, from Wiseco or another performance piston manufacturer?
 
Joined
Sep 3, 2007
Messages
169
L.A.B. said:
Tulsaalva said:
The bolt on the large side is so tight that the wrench rounded the corners.
They are often very tight. The "large side" of the pump is the scavenge side.
"Very tight" is a good description. I've "boogered up" the head so much now that I'm sure it's in there to stay. Even if I did get it out, it's doubtful, I imagine, that I'd be able to find a replacement.

Tulsaalva said:
In the meantime the bike has another challenge that may have contributed to the breakdown by lowering the oil level in the primary case.
I wouldn't have considered that to be a serious oil leak (not by Brit bike standards anyway) and it is doubtful that an occasional drip of oil from the primary case would have contributed to any engine damage, unless the level of oil in the frame reservoir had been allowed to drop to a dangerously low level as a result?
I had the primary gasket sealed. The leak is at the crack I described. I was thinking that the primary case may have been depleted during long idle times in the winter. Seventeen might have started the bike on a pretty winter day when there wasn't enough oil in the primary. Not true?

Tulsaalva said:
Next, I'll learn whether I only need rings or pistons as well. Would anyone like to offer an opinion? Stock Triumph or after-market? Keep in mind that "better than new" is preferred.
I'd still opt for standard replacement Hepolite/AP/Federal Mogul (or whatever else they may be calling themselves this week?) pistons and rings, no doubt other choices are available on your side of the pond, from Wiseco or another performance piston manufacturer?
Wiseco has been a good name here for many years. I used to know the people who owned the company when I was a manufacturers' rep in the industry. I'll ask LaNelle on Tuesday what's available and what the other Anglophiles most often use. I like to support her shop because she does such a good job of keeping parts that we need. Besides, her husband and I were high school classmates about a century ago. :)

Thanks, Les!

Al
 

L.A.B.

VIP MEMBER
Joined
Nov 20, 2004
Messages
15,551
Country flag
Tulsaalva said:
"Very tight" is a good description. I've "boogered up" the head so much now that I'm sure it's in there to stay. Even if I did get it out, it's doubtful, I imagine, that I'd be able to find a replacement.
The bolt (screw plug) ball and spring should be available as a spare (was part 70-2360, 71-7314 now I think?)

If I'd have found the plug to be extremely tight, then I would probably have held it by the squared flats in a vice/vise, and then tried to unscrew the pump away from the plug with an adjustable spanner/wrench tightened across the pump body?



Tulsaalva said:
Seventeen might have started the bike on a pretty winter day when there wasn't enough oil in the primary. Not true?
If the primary did dry out because of leakage over a lay up period then the primary chain would have been a bit dry for a short while after starting up maybe, I'm not exactly sure how much harm would have been done?
 
Joined
Sep 3, 2007
Messages
169
L.A.B. said:
Tulsaalva said:
"Very tight" is a good description. I've "boogered up" the head so much now that I'm sure it's in there to stay. Even if I did get it out, it's doubtful, I imagine, that I'd be able to find a replacement.
The bolt (screw plug) ball and spring should be available as a spare (was part 70-2360, 71-7314 now I think?)
Great! I'll ask LaNelle if she can find it! Maybe I can save a bunch of money and still have a good pump!

If I'd have found the plug to be extremely tight, then I would probably have held it by the squared flats in a vice/vise, and then tried to unscrew the pump away from the plug with an adjustable spanner/wrench tightened across the pump body?
Yep! I tried that. More of the bolt broke off. I even thought it might be a reverse thread for some reason (although I would think the manual would have mentioned it...) but it was too late to try that. Probably a good thing. If I can find the part, perhaps I'll try a "Difficult Out," more commonly known as an "Easy Out." :)

Tulsaalva said:
Seventeen might have started the bike on a pretty winter day when there wasn't enough oil in the primary. Not true?
If the primary did dry out because of leakage over a lay up period then the primary chain would have been a bit dry for a short while after starting up maybe, I'm not exactly sure how much harm would have been done?
Okay. Then I think the culprit was the scavenge side of the pump. I'm hoping the pistons only need new rings. I'll let y'all know.

Thanks again!

Al
 
Joined
Oct 5, 2008
Messages
1,693
A lot of times a weak area can be repaired way better than new by a good welder. The new oil pump will be a good investment I'm sure.
 
Joined
Nov 6, 2008
Messages
502
Country flag
hi tulsa,the oil pump maybe the culprit if it was,nt scavenging the sump, excess oil in there would give the impression that the rings or pistons or a worn bore was causing the oil burning you described earlier i would fix the pump first
 
Joined
Sep 3, 2007
Messages
169
Cookie said:
A lot of times a weak area can be repaired way better than new by a good welder. The new oil pump will be a good investment I'm sure.
I understand that the weld is stronger than the original metal, Cookie, and the guy I plan to use comes highly recommended. A lot of the guys who hang out at LaNelle's have used him and rave about his work.

I have a Tig welder myself and use it from time to time but this calls for someone much better than I am.

Thanks!

Al
 
Joined
Sep 3, 2007
Messages
169
chris plant said:
hi tulsa,the oil pump maybe the culprit if it was,nt scavenging the sump, excess oil in there would give the impression that the rings or pistons or a worn bore was causing the oil burning you described earlier i would fix the pump first
Thanks for the explanation, Chris. I am going to update the pump, but I also have to address the uneven and low compression. I'll definitely fix it right. A thirty year old bike deserves nothing less, in my opinion.

Al
 
Joined
Sep 3, 2007
Messages
169
Apparently one of my posts faded away into Cyberspace.

I've removed the errant bolt with a vise, an Easy Out, and a 2.5 foot extension. I don't like either seat. The large side is off-center and elliptical. The small side doesn't look much better, but seemed to seal when I tested it. Nevertheless, I'm going to buy the new pump.

Al
 
Joined
Sep 3, 2007
Messages
169
swooshdave said:
Tulsaalva said:
It looks like the "School of Hard Knocks" tuition has been increased by several hundred dollars.
Education is never cheap or easy.
I've heard it said, Swooshdave, that the problem with learning from experience is that one gets the test first and the lesson afterwards. :)

Al
 
Joined
Sep 3, 2007
Messages
169
chris plant said:
Tulsaalva said:
Apparently one of my posts faded away into Cyberspace.
sorry tulsa, my mistake i was obviously thinking of something else
I don't understand your unnecessary apology, Chris. I wrote a rather long post that had nothing to do with you but it didn't appear in the thread. My guess is I forgot to click "'Submit." :) I've done that sort of thing before.

Al
 
Top