1725cc Rebuild

[Hillman]

Its been done.

Before I converted my SII to use an SV tach, I had a 1725 engine and a complete (with tach drive) SII dstributor running the stock mechanical tach.

My SII with 1725 is running with an early dizzy and cable tach as was rr's.
I didn't do the swap, but I think it all stock, possibly using the early oil pump (or parts of it) as well.

The car is in winter storage but over the next few days I can look at it, if you like.

Al

 

[mamoose124]

Conversion of SV dizzy to work with SI tach.

Thanks to all of you for your input on this issue. Since I'm not a mechanical wizard, I'm thinking if Nisonger Instruments can convert an SII Tach to electronic function, that is the way for me to go. I will check that out first. My second alternative (if I understand things correctly) is to use my SII dizzy and replace its drive gear with the SV dizzy drive gear so it will mesh with the SV cam drive gear.

Let me know wheather or not I have the second alternative properly described.

Thanks again guys for the advice.

 

[RootesRacer]

My second alternative (if I understand things correctly) is to use my SII dizzy and replace its drive gear with the SV dizzy drive gear so it will mesh with the SV cam drive gear.

Let me know wheather or not I have the second alternative properly described.

Thanks again guys for the advice.

No, this is not the case.
The dizzy is driven by the oil pump "gear if you will" that happens to be too short when the pump is a 1725 and the distributor is an SII.

You cant just change the oil pump drive "gear" becuase the correct "tall" one has a different number of teeth than that which is on the camshaft.
This results in damage to the cam and pump gears and the engine couldnt have run without a 1/1 cam to distributor drive ratio anyhow.

Converting the speedo to electric would be the easiest option for you though I have never heard of this as a service before.
For me it was easy enough to machine the bits needed to couple the otherwise incompatible parts mechanically.

 

[hartmandm]

Converting the speedo to electric would be the easiest option for you though I have never heard of this as a service before.

Check out http://www.nisonger.com/mechanical-tachometer-conversions.htm

Mike

 

[65beam]

rebuild

Thanks to all of you for your input on this issue. Since I'm not a mechanical wizard, I'm thinking if Nisonger Instruments can convert an SII Tach to electronic function, that is the way for me to go. I will check that out first. My second alternative (if I understand things correctly) is to use my SII dizzy and replace its drive gear with the SV dizzy drive gear so it will mesh with the SV cam drive gear.

Let me know wheather or not I have the second alternative properly described.

Thanks again guys for the advice.

Nisonger has our original tach for the RHD LeMans and are converting it to electrical. The car will be converted to a negative ground system so they will set the tach up for that. They can build it for either negative or positive. They do eliminate the loop of wire found on later tachs. FYI, the cost is $375.00. The turn around time right now is 5 to 6 weeks due to the holidays.

 

[mamoose124]

Conversion of SV dizzy to work with SI tach.

No, this is not the case.
The dizzy is driven by the oil pump "gear if you will" that happens to be too short when the pump is a 1725 and the distributor is an SII.

You cant just change the oil pump drive "gear" becuase the correct "tall" one has a different number of teeth than that which is on the camshaft.
This results in damage to the cam and pump gears and the engine couldnt have run without a 1/1 cam to distributor drive ratio anyhow.

Converting the speedo to electric would be the easiest option for you though I have never heard of this as a service before.
For me it was easy enough to machine the bits needed to couple the otherwise incompatible parts mechanically.

Thanks for the correction, RootesRacer. I have talked to Nisonger and they do offer the servic of converting a mechanical tach to electronic. So, I'm going to do that and forego all the necessary gear swapping required to fix it mechanically.

I will keep you posted on my progress with my rebuild 1725cc engine.

 

[hartmandm]

My recollection is the thing looked like a customization to a series 2 spacer / tach drive (see attached photo). The series V distributor ends up sitting a bit higher than normal.

I like your plan to modify the tach to be electronic. Anyways, I did get the photos from my brother. It is a modification to the oil pump. Some images are attached.

Mike

 

[65beam]

rebuild

Thanks to all of you for your input on this issue. Since I'm not a mechanical wizard, I'm thinking if Nisonger Instruments can convert an SII Tach to electronic function, that is the way for me to go. I will check that out first. My second alternative (if I understand things correctly) is to use my SII dizzy and replace its drive gear with the SV dizzy drive gear so it will mesh with the SV cam drive gear.

Let me know wheather or not I have the second alternative properly described.

Thanks again guys for the advice.

The LeMans tach came in the mail today. Nisonger converted it to an electronic unit . Three wires and set to be used with a negative ground system. They also can set it up for positive ground systems.

 

[mamoose124]

The LeMans tach came in the mail today. Nisonger converted it to an electronic unit . Three wires and set to be used with a negative ground system. They also can set it up for positive ground systems.

Thanks 65beam for the information and photos. I am planning to do the same thing to my tach when the time comes and it is reassuring to see others doing it. Let us all know if it works flawlessly.

 

[Jim E]

once you get the tach how you want i would send the cam lifters and rockers to delta, unless you have a new oil pump and even if you do would lap it to close to zero then head work hardened valve seats at least a three angle vavle job and port work.. Leroy here in columbia knows these haads of course a recorded radiator.. standard crank in Charlotte is good ... the you can stoke or destroke with chevy rods

 

[Jim E]

the destroked motors always ran better IMO

 

[alpine_64]

once you get the tach how you want i would send the cam lifters and rockers to delta, unless you have a new oil pump

On point E.

 

[mamoose124]

once you get the tach how you want i would send the cam lifters and rockers to delta, unless you have a new oil pump and even if you do would lap it to close to zero then head work hardened valve seats at least a three angle vavle job and port work.. Leroy here in columbia knows these haads of course a recorded radiator.. standard crank in Charlotte is good ... the you can stoke or destroke with chevy rods

Thanks for the information Jim. I am planning to send the cam and rockers to Oregon Cam in Vancouver. I am going to purchase a new oil pump but I don't nderstand what you mean by ". . .would lap it to close to zero . . ." Can a reglar machine shop "harden" the valve seats? And what might that cost? I don't know what a "three angle valve job" is either. Could you explain? I have already had my radiator recored at cosiderable cost. As you can see from the above, I am a novice when it comes to engine overhaul.

Thanks for the information. I will do some ressearch and check this info out.

 

[Alpine 1789]

Mike: If you are planning on sending it out anyway, I strongly recommend you consider Delta. If you search this site you will find many happy customers and, more importantly, they know our cars and have multiple Alpine grinds ready to go. The most popular for street cars is their KB grind, which gives you a slightly lumpier idle but makes the car more fun to drive.

There is nothing all that complicated and special about Alpine engines, but they are different and it helps to work with shops who have experience. If you are going to have head work done, I would definitely urge you to consider Jim's recommendation of Lee in Columbia. I used him about 5 years ago and was very happy with his work. Here is a thread from the time: http://www.sunbeamalpine.org/forum/showthread.php?t=16707 All but the initial post - which contains Leroy/Lee's contact details - deals with issues and questions I had when reinstalling the head.

 

[mamoose124]

Jim,

Now that I know that Delta Cams specializes in Alpine cams, I will certainly send my cam and rocker arms to them. Obviously, the postage difference between Vancouver, and Tacoma, WA would be negligible. I will call them for details before shipping out my parts.

While I normally prefer working locally with a machine shop (things should move along faster with direct contact), I do like the idea of working with a shop that has considerable experience with Alpines. I have already committed major funds to this car some of which was misspent due to unprofessional workmanship by “supposed” British car restorers. So I am happy to consider Jim's recommendation of Lee in Columbia, South Carolina even though freight costs will bring the price above that of using a local machine shop.

I read your thread illustrating your rebuild with interest. In fact, I took copious notes in preparation for my rebuild. Let me compliment you on your thread: it is the most well-organized thread I have read on any forum. You not only organized your thread well, you have a knack for asking the right questions. The answers given by our SAOCA members are spot on and will help me with my rebuild (thus the copious notes). In this regard, would you be willing to have me PM or email you as I move through the rebuild process? I would value your council highly.

What exactly, did you have Lee do to your head? Did you hard seat and port the valves? What was done?

Finally, what was the final outcome for your rebuild? Your last post was dated 2011 just as you were having your radiator re-cored. I feel as though I am waiting for the last installment of a television series and am anxious about the outcome.

 

[Alpine 1789]

I am always happy to help Mike. You can PM me or send me an email via the forum. Or, we can just 'talk' here so that others can contribute and/or learn from the discussion. But, I do need to warn you that I am probably not much more knowledgeable than you; just a little more experienced at this point. My 1789 engine is the one and only engine I have ever built. Almost all that I know about building an Alpine engine I learned here from other SAOCA members. In particular, Jim E was incredibly helpful to me and electronically held my hand every step of the way.

I documented my engine build in an article for the club's old newsletter, The Marque. That article is available through the SAOCA Info tab on this website. Here is the direct link: http://www.sunbeamalpine.org/alpine_marque/issue_11.pdf If you are considering the Chevy Rod modification - something I highly recommend; everyone I know who has done it was happy with the results - you should also read the article Jan Servaites wrote a few months later: http://www.sunbeamalpine.org/alpine_marque/issue_14.pdf. Jan has probably forgotten more about Alpine engines than I will ever know and his rods were slightly different from mine, so careful measurement is important.

And, while I am linking to old Marque articles, Jim E's "More Power" article should be required reading of anyone looking to enhance their engine: http://www.sunbeamalpine.org/alpine_marque/issue_13.pdf

So, now on to your specific questions. My head was originally re-worked by Jim, who did the Vizard Mod on it. (Also documented on this site. See http://www.sunbeamalpine.org/downloads/Vizard Mod.pdf) The head had been damaged by the coolant leak so the first thing Lee did was repair the damage. He then did some further porting work to make it flow better. In all honesty, I don't know how different it was in the end from what Jim did. My guess is that it was primarily just a little more 'polished' in the sense that Lee has the equipment to fine tune it and get each cylinder maximized and exactly the same. He did install hardened seats and such.

As for the rest of the story, I am sure that is documented here somewhere, but the new radiator worked perfectly. I never really had trouble with the car overheating, but I have so much time and money invested in the engine that the extra expense seemed like cheap insurance. I drive the car almost every day in nice weather and continued to tweak it in the ensuing years. Many long time members here still remember my flirtation with DCOE carburetors. I loved the way they made the car respond and sound and will one day try them again, but I could never get them properly synchronized and finally gave up. Unfortunately, I realized after months of trying that the problem was with my manifold, not the carbs, which is why I will try again. The most recent change is to a Weber 38 DGES downdraft carb, which I really like. (http://www.sunbeamalpine.org/forum/showthread.php?t=23364) I have a couple of projects on the drawing board (electronic fuel pump and some distributor modifications/changes) but can't seem to find the time to get to them. That is what happens when you retire. All the time in the world evaporates very quickly. I don't know how I ever found the time to work!

Have fun and fire away with questions. This club is the best thing that has happened to Sunbeam ownership, at least in my 40 years of experience!

 

[mightyohm]

I'm also interested in the adapter necessary to fit a series II distributor to a 1725 oil pump. Anyone have a drawing or dimensions?

 

[alpine_64]

I'm also interested in the adapter necessary to fit a series II distributor to a 1725 oil pump. Anyone have a drawing or dimensions?

I used to have photos of the procedure on my webshots posted here.. You also need to modify the sump baflle for clearence if you use the later style pickup .

Ill see if i.can find the photos