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Heading to Mongolia

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Michael S Avatar
Michael S Michael Salter
Dwight, ON, Canada   CAN
If the exhaust valves are longer and everything else is the same then the seat pressure on the exhaust seat will be lower.
The big advantage of the 100 engine is its low end power.
I would suggest that a long as you have something close to the original specs don't worry about it. Higher spring pressures means higher valve gear stresses with the associated possibility of failure of lifters and cam..
It is unlikely that you will ever want to pull much over 5000 R.P.M. and the standard valve train can handle that.
In my experience longevity of the cam and lifters will turn out to be much more important than being able to impress the spectators with how many revs you can pull :-)
I would recommend reading this : http://www.netbug.net/blogmichael/2006/12/01/cam-issues/



Michael Salter
Technical Chairman (Big Healeys)
Austin Healey Concours Committee

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Craig Clifton Avatar
Martinez, CA, USA   USA
Giles, are you certain that the exhausts are longer? Remember, the small diameter valve is the exhaust.
I have my original head on the bench and the 4 intakes are all about the same height in the head. The exhausts are all about 1/16" lower than the intakes. Mind you there have been a couple valve jobs over the years.

Regarding the spring pressure, any good shop should measure all your springs prior to install. They should look at "free length", pressure at "installed height" and , if they are really a good shop, distance to "coil bind" at full lift. They can compensate for variations in "installed height" and seat pressure by adding/subtracting shims beneath the spring.

I am a bit distressed at the condition of your core plugs. It appears they were installed using the common, but still incorrect, method often found on the internet=ball peen hammer on plug, struck by another hammer. Since the perimeter of the plug has not been flattened, they will not have reached the intended outward pressure to hold them in place securely. A correctly installed dish-type plug should be flat with a very mild dimple in the center.
For information about the correct tool(easily fabricated by anyone with a lathe) look HERE

I have made such a tool for the larger plugs on a 100 and tested it out. If you would like pics of tool and installed plugs, I can probably get to that tomorrow.

Qldelsie Silver Member Giles Cooper
Benowa, Queensland, Australia   AUS
Thanks Craig.
Re the valves, No, the inlet valves are the longer ones - My mistake.
Yes, I understand you can adjust / increase the heights of the springs with shims, but if the pressures are already higher than the manual states before any shims are added, then the only way to reduce the pressure is to set the valve seat lower. And we are loathe to do that. Yes, we have checked all the spring pressures at the various heights - That is what prompted my original question - They were too high. Shims would help if they pressures were too low, but no good if they are too high. That is the key to the problem - We rely on vendors to supply us with valid / correct parts, but if there is one thing we have learned over the past 12 months, the number of parts that are downright incorrect, even when supplied by supposedly reputable suppliers, is endless - Don't even get me started on THAT subject !!!

Re the core plugs, whichever method is chosen, it is a bit late to do anything about it now as our plugs are already in, and strapped. We are in no position to start taking them all out again and ordering new ones even if we decided to !
Out of interest, I quote from the page you mention - “If only a few plugs are to be installed, the best tool for setting them is a short piece of cold drawn shafting 8 or 10 inches long and of a diameter slightly less than the diameter of the plug to be set. By placing it perpendicularly over the plug, and striking the shafting one or two blows with a fairly heavy hammer, the plug can be set down sufficiently to not quite a flat position”. The difference between using this special tool or alternatively the flat face of a hammer would appear to be minimal, assuming the diameter of the two were similar ?? Whatever, ours are in and strapped, fitted by people whos specialise in older British Cars. If you follow our blog during the next 12 months, you will find out (as will we !) whether iur plugs are up to it or not ! Either way, I appreciate your input, and will bear it in mind on future rebuilds !

Cheers,
Giles



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Qldelsie Silver Member Giles Cooper
Benowa, Queensland, Australia   AUS
Michael, we certainly won't be revving the engine to try and impress any spectators !! Our plan is to finish, and we will accept any position if we manage to drive unassisted into Place Vendôme in Paris on July 9th. If we make it through Mongolia and Kazakhstan, we may have a chance to achieve that. We are under no illusions whatsoever about the enormity of our undertaking - You won't see a Healey driven more respectfully or conservatively, I can assure you !! Most of the time, anyway !!
And as far as the head is concerned, we are continuing to rebuild the original head that is under discussion re the valves, but we have luckily managed to obtain a new alloy head from DWR and we will be using that. So our concern over the valve lengths and spring rates is now only to ensure it is rebuilt correctly - The pressure is off in that regard ! Sigh of relief !
Giles



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Craig Clifton Avatar
Martinez, CA, USA   USA
Giles, regarding the core plug installation, many of the "internet sources" (forums, etc.) seem to suggest that the ball end of a ball been hammer be placed over the center of the plug and then struck with a second hammer. It is that highlighted part that I object to. This usually just results in a dimple in the center and NO flattening of the perimeter. The alternative method you quoted would be much, much better than the ball peen hammer method. When I rebuilt my 100 engine in 1975, the machinist told me to use a 1/2' drive socket and extension with the socket reversed so that the flat side was against the plug. I was told to do this in 2 steps. First, use a socket roughly 1/2 to 2/3 the diameter of the plug to set the plug. Second, use a socket as large as will fit in the block opening to flatten the perimeter. This technique, as well as using the prescribed tool on the page I linked, will result in a plug that has a gentle, minimal recess in the center. I suspect a lot of people think the "dimple" or "recess" is the key to proper installation, when the important thing is flattening the plug as much as possible.

As far as time is concerned, replacing them while engine is on the stand is probably less than a 2 hour proposition. The front plug cannot be replaced with the engine installed. The others are a B***h to replace and the rear 2(end of block) require trans tunnel removal and only one is a straight shot. So the question here is do you take a few minutes to do it now or struggle mightily if one comes out on the journey? I (and you) know what my choice would be.

By the way, I have nearly 40 years in the automotive repair world. I have replaced more core plugs than I could ever begin to count. Some are easy, most are not. I would much rather do them on a stand than in the car. I replaced all of mine, except for the one behind the engine mount, last summer due to leakage of one of them. It was a project. I don't look forward to eventual replacement of the hidden plug. Perhaps I'll build and install my spare engine when that time comes. smiling smiley

Craig

Qldelsie Silver Member Giles Cooper
Benowa, Queensland, Australia   AUS
Craig, while I am sure that it may only take 2 hours to change the plugs while the engine is out, that is not the issue. We would need to order new ones from overseas, and that takes a couple of weeks minimum. THAT is the time delay for us, not the installation.
I am interested in your comment that you replaced yours because one was leaking. Was it leaking because of incorrect installation, or because it had rusted / corroded over time ? How long had they been in the engine - Since your rebuild in 1975 ?
Giles



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NOHOME P P
O, ON, Canada   CAN
1967 MG MGB GT "Maggie (GT From Hell)"
Been following this since post #1 and realizing that the start date is June 2nd 2019, I would say that the way project time goes by, that is not all that too far into the future.

By when does the car have to be on the ship?

Love the Mongolian Cloverleaf intersections!



Pete

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Craig Clifton Avatar
Martinez, CA, USA   USA
Giles,
I replaced the core plugs because one had developed a leak. Upon removal, I found the back of the plug badly corroded. When I removed the rest of them, they were also corroded pretty badly. They were the plugs I installed in 1975. Had I done then, what I have done pretty much ever since, coat the back side with a sealer(permatex red usually)I suspect they would have been OK. These were a high quality brand, in steel, from a REAL auto parts store, not the cheapo stuff available today.
I replaced all of the 1.625 and 1.188" with brass plugs. Well, all but that nasty little devil behind the motor mount. smiling smiley

Craig

Michael S Avatar
Michael S Michael Salter
Dwight, ON, Canada   CAN
I would concur regarding brass core plugs and use them exclusively now.
They are sometimes difficult to source but large marine suppliers are a good source as they are always used in marinized engines.



Michael Salter
Technical Chairman (Big Healeys)
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panelbeat Dave C.
N/A, N/A, USA   USA
Giles, If you haven't finalized your electrical plan then I might make a few suggestions. When I converted my BJ7 Healey to an alternator I used a GM Delco unit from approx 1994/95 vintage. My reasoning is that they are probably
available anywhere. (yet maybe not where you are going.) The mounting for it is available from Hendrix Wire Wheel in the States. Also Alan Hendrix is a very knowledgable guy on all things Healey and a pleasure to work with. I removed the firewall mounted voltage regulator and used a terminal strip in the same location to connect the necessary wires. (the alternator having an internal regulator). When it comes to wire size and charging amperage, I is important to up the wiring to handle all that the alternator can put out. The reason for this is that if the battery turns up dead or near dead or just severly depleted the alternator will try to put out its max charging current to replentish the battery. Even tho you upgrade the wire from the battery to the solenoid location that leaves the charge wire from the altenator to the regulator location definately undersized. I believe the existing wire on the generator is at most a number 12. It is only good for 20 amps. If the alternator goes to max amps to try to recharge a depleted battery the wiring harness will be overloaded and burn up. What I have done is to install a # 10 stranded copper wire from the alternator "BAT" terminal to the solenoid location which electrically parallels the existing wire in the harness. the #10 wire is rated at 30 amps but it will carry more so you are hedging the potential that it will be overloaded. I admit that it is somewhat of a compromise but putting a larger wire from the alternator to the solenoid is problematic. I replaced the battery wire that runs under the car to the battery with a # 2 stranded copper wire that I got at Summit Racing in the US. It is what is commonly used in the Drag Racing industry. I forget the rating of the #2 but it is heavy and super insulated so as to protect from abrasion. The alternator will not outperform this wire. I have two auxiliary power plugs mounted on the bottom edge of my parcel shelf. One for cell phones/I-pad and one for GPS. You won't hear the music anyway. I have been running this system for 4 years now and the electrical system with driving lights, etc works flawlessly. I also have 2 modern style fuse boxes. One is from the ignition switch which was all the little green wires from the bottom of the 2 original fuses and the other fuse box is supplied from the wire that fed the top of the original fuses with is always on and was intended for auxiliary equipment such as radio and driving lights. I'll try to attach some pics.


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panelbeat Dave C.
N/A, N/A, USA   USA
Giles, one more thing. don't use a 1 wire alternator. Many people think it is a good idea because it eliminates some wires. Many hot rodders and custom car people like them because when eliminating a few wires it makes their engine bays look prettier. But one wire alternators can and many times do have trouble maintaining a good charge on the battery. It is because their voltage sensing capability is right at the alternator not back on the harness where there may be some voltage drop due to load or smaller wires. Also with the original healey wiring harness if you use a 3 wire alternator like the original GM then you can keep your ignition charge light in the dash board. I suppose it goes without saying that you should install a volt meter in your dash as well. If the voltage ever drops below 12volts you'll know you have a problem. Good Luck, Dave.

Qldelsie Silver Member Giles Cooper
Benowa, Queensland, Australia   AUS
Pete, we need to have the car in Peking by end of May, so will probably leave here (Aus) about end of March 2019. Shippers will tell us when they want it. But you are absolutely right - Time is strting to go by VERY quickly !

Great information and pics Dave C, thank you. Yes, we are upgrading the wiring to suit the bigger alternator. The wiring in the car is not original anyway - A new loom was fitted when the car was converted to RHD after it arrived in Aus from California. And it had an alternator previously, but not as big as the one we have put in !!

Re Core plugs - We work on the theory that steel core plugs are intended as sacrificial, and should be expected to rust out any time after 10 years, so would normally change them at 10 year intervals. My understanding is that they work as a sacrificial anode, and are intended to corrode eventually, thus saving other parts from corrosion. So for yours to last since 1975 is pretty good going, I would suggest ! Surely if you coat the back of them so they do not rust, then you are going to transfer the corrosion problem to some other engine part ? Just surmising - There seem to be more different and conflicting opinions on this item than there are on how to spell "Austin-Healey 100" correctly !!!!

Giles



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panelbeat Dave C.
N/A, N/A, USA   USA
Giles, awhile back you talked about your SU fuel pumps. Just to let you know that I have 2 identical SU fuel pumps mounted in my BJ7. I have mounted them exactly opposite each other where-by the original one is on the right side and in the original position and the other one is on the left side mounted just like the the original just opposite. I HAVE PLUMBED THEM IN A SERIES CONFIGURATION. One pump pushes thru the other. I have wired the pumps with an interlock circuit where-by one pump can not come on unless the other one is off. This is to ensure that each pump can be used as a back-up pump. they are not there to increase capacity but only to be back ups. Each pump can prime itself with good suction to the tank which is an original tank. As I use the car I alternate which pump I will use that day. As said, which ever pump is in the energized position it will prime the system very well even tho it is sucking or pushing thru the other. the new fuel line is copper all the way to the carbs and is mounted in the original position along the right frame rail. I don't really have very good pics about this but I do have one pic showing one of the pumps. I brought this up to explain that 2 SU pumps will suck and pull quite well even when mounted in series to each other and mounted one on each side. Dave.


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Qldelsie Silver Member Giles Cooper
Benowa, Queensland, Australia   AUS
Interesting Dave. We have fitted ours slightly differently - in parallel, I guess you would call it. We decided not to have one pump pushing through the other because if one pump gets blocked up, then you wouldn't be able to "push through it", would you ? (That is meant as a question). So ours are plumbed and wired up as per the attached pics, with either or both the pumps able to be run at once, but both on independent lines, so that if one gets blocked, then the other can be used until we have time to clean the blocked one. Mind you, with our additional filter, we hope that won't be necessary !! Individual switches will be mounted on the dash, and each pump will be separately fused.
Underneath the fuel pumps is a kind of alloy "manifold" - The fuel pipe from the tank comes into this manifold, and then each pump has a connection to that manifold, so they have separate lines.
If some of the lines look a but askew, that is because they are not all yet hooked up ! But basically the items are located in the boot to keep them out of the way of flying rocks and mud near the rear axle, and are set low down to keep the pump head low. This would make them hard to work on, you might think, but no !! The fuel pumps themselves can be removed just by undoing two upper bolts on the backing panel, because underneath the backing plate just slots into a recess which holds it in place once the upper bolts are tightened. Additionally the fuel filter is separately mounted and designed to be quickly removed and either the filter changed or water emptied from the clear bowl when the filter is outside the boot, thus not spilling fuel inside. All fittings are threaded, and while the fuel hoses will have hose clamps on them, these will not need to be undone - Just unscrew a threaded fitting and its done, and all fittings are the same size, so only one spanner needed.
And in theory, we can run both pumps together - Maybe if at altitude or for whatever reason - We do not intend to, but could if we needed to.
Our fuel lines will run inside the car, again for protection, but we will use steel inside the car, not copper.
All interesting options, and thanks again for your input. We really value all of this so much.
Giles



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Qldelsie Silver Member Giles Cooper
Benowa, Queensland, Australia   AUS
In reply to # 198152 by Craig Clifton Giles,
I replaced the core plugs because one had developed a leak. Upon removal, I found the back of the plug badly corroded. When I removed the rest of them, they were also corroded pretty badly. They were the plugs I installed in 1975. Had I done then, what I have done pretty much ever since, coat the back side with a sealer(permatex red usually)I suspect they would have been OK. These were a high quality brand, in steel, from a REAL auto parts store, not the cheapo stuff available today.
I replaced all of the 1.625 and 1.188" with brass plugs. Well, all but that nasty little devil behind the motor mount. smiling smiley

Craig

Understood. Which is why we work on a 10 year life for core plugs, because they are sacrificial, and we expect them to rust. So given that expected life interval, and the fact yours lasted some 40 years, I think our steel ones will be just fine !! Fingers crossed, anyway.
Giles



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