Ryland3210

I have also heard that WD40 works, and includes lubricants to help prevent washing off the oil film on pistons and cylinders. I don't think that is quite as effective a starting fluid as those made for starting engines, but it has worked well enough to get my tractor running when necessar. I don't know if there are silicones in WD40, but I suspect there are, just from the smell. If so, there may be some interaction with motor oil. I personally would avoid using straight ether for fear of the washing off potential.

Would ordinary alcohol do as well?

Our practice on industrial machinery where steel screws are used in tool steel blocks, is to have at least one diameter of thread depth. At that point, the shear stress is low enough such that the screw will fail in tension before the threads strip. I take exception to only one part of Mattress's commentary. I believe the maximum shear stress occurs nearest the surface of the block, rather than at the extreme end of the bolt. I agree with the domino effect failure mode, but believe it starts from the surface, not the bottom. The result is the same either way in a catastrophic failure. Other evidence of the threads nearest the surface yielding first is the common practice of countersinking to avoid the deformation of those threads above the surface. We do not use gaskets in our applications, only O-Rings. Our goal is to achieve metal to metal contact between the mating surfaces, so to prevent any possibilty of thread yielding causing an interference, we counter bore about one or more thread pitches. That assumes one still has enough thread depth left in the hole. The counterbore also serves as a convenient pilot for the screw. B&T, a machine builder of die casting machines in years past, had a patented tie bar nut design that compensated for the stress concentration on the threads nearest the tension end of the tie bar. These highly stressed, cyclicly loaded tie bars ranged in size from 2.5 inches to over 13 inches in diameter. The threads on the nuts were tapered to distribute the load over several threads. They were able to guarantee their machine's tie bars would never break as a result, a significant marketing advantage. It is easy to cross thread aluminum female threads with a steel screw that has a buggered up end. It's good practice to inspect the screw, and file or grind the first thread if dented or otherwise defective. My practice is to always start the screw/nut by hand first.

Yes, I considered that too, so I checked my Ford manual before sending the pattern, to see which it specified. I do think my sequence has a slight advantage in that it avoids the twisting of the head from your 3 to 4. One could argue that the Ford pattern causes twisting when moving diagonally as well, but in that case, it first occurs after more screws are tighten, therefore has less of an effect. It probably is hair splitting, so long as the stages are observed. I believe the four stage process could be used with either pattern. If only two stages were used, I'd worry a lot about the pattern, and not getting a proper seal. At least three stages ought to be used, and the more the better.

Go for it! Studs usually have coarse thread for the block end and fine thread for the nut end. The best kind of brass nuts are fine thread and extra long to make up the lower strength than steel. If they are long enough so the stud is flush with the end of the nut, there is no steel proud of the nut to rust.

Hi Ratchethack, My comment on temperature was a bit of my tongue in cheek humor. I really don't believe the coefficient on thermal expansion is a significant factor. I managed to resist the temptation to specify the relative humidity and barometric pressure. I don't understand the value of measuring the amount of oil coming out. That will vary depending on consumption since the last oil change. The reason I cared about oil volume was only a means to an end, calibrating the dipstick. It was a one time only experiment. The logical place to start was to see where the full mark ended up when carefully draining, then adding 3.5 liters as Guzzi specifies. Having done that, as I said, I'll of course be using my calibrated dipstick to maintain oil level henceforth. Had the results been above the gasket or suspciously low, I would have done some more investigating. As it happens, the 3.5 liters was near ideal, absent a sloppage sheet. Right now a sloppage sheet is not an option for me, as the warrantee is still in effect. If I get one, I'll probably raise the oil level as Pete has suggested. I was careful to avoid double dipping, and took several measurements. I can get as obsessive as I feel is necessary to "do it right the first time" so I never have to do it again. Glad to hear how Pete's sloppage sheet guides the dipstick. That's eliminates the potential source of a major error.

Things will be all right as far as the threads are concerned, and the screw will not fail either. The worst case on tightening would be the case of installing the head from scratch, and tightening one of the screws at one end all the way, which compresses the gasket at that point more than normal, then tightening the screw at the oppossite end. That will use the head as a lever against the gasket near the first screw, and have the tendency to deform the head at that point. Starting at the middle and working to the ends avoids that lever effect. Tightening them all in stages keeps the head's pressure on the entire surface of the gasket more uniform as it compresses a little more with each stage. If there is any part of the stud you can grab onto, after applying penetrating oil and leaving it be for a few hours, I've used stout vice grip pliers, got them as tight as possible and tried that. If necessary, I file or grind flats to give the vice grips a better grip. If the stud is threaded into aluminum, it can really get stuck hard due to the dissimilar metals combined with heat that eventually burns off any lubricant that might have been on the stud when installed. As Martin says, then it's easy out city. In my case, that's only worked about half the time, but worth trying before you resort to drilling out the stud. When I have to do that, I center punch the stud as close to dead center as possible, to help the drill bit to stay in the center. Then comes the fun of getting the remaining pieces of stud remaining out. I apply "Never Sieze" to studs like that when installing them. Then lock washers and brass nuts on the steel stud to make later repairs easier.

I believe it is quite easy to strip the threads in an aluminum block because the torque/preload specs are going to be far lower than with ductile iron blocks. It better to have studs in the block and nuts with washers on top of the head to tighten. That way, the studs can be threaded as far as practical into the block first. There is a saying in mechanical engineering circles that you can tighten to failure, but you cannot tighten a screw to fail. In other words, the fastener snaps or the threads strip during the tightening procedure before the fastener can be loaded enough to cause failure in service. As long as the bolts were orginally torqued to spec, I believe you could safely tighten them to the torque spec. for your specific motor, PROVIDED you follow the proper sequence, which will be specified in the service manual. If that isn't available, usally a very thorough but reliable sequence is as follow: Do not loosen any screws. Start from the middle of the head, tighten to 30% of the the torque specification. Of course, some of the screws will already be tighter than that. If so, move to the next. Alternate from top to bottom, while working your way out to the ends of the block. Same again at 50%, 80% and 100%. The pattern would look something like this on a ten screw pattern: 8 4 2 6 10 7 3 1 5 9 This procedure reduces the chance of warping the head. When installing a new gasket,, the screws should be checked again after a few hours of normal driving. This is rarely done on new cars these days. In the old days, gaskets would compress a good deal, so this was considered good practice. Even today, I just replaced all the seals and gaskets in '57 Ford engine. Even with very careful tightening, I found that after one 50 mile trip, a number of screws took another good 1/8 to 1/4 turn to return the preload to the spec. Because it has solid lifters, that meant checking the valve clearance all over again. Taking care of this now, will virtually guarantee my head gaskets will never leak, and I don't have to worry about the valve clearance for a very long time. You probably know much of this, but I didn't want to take the chance of leaving anything out, not knowing your level of knowledge. If all else fails, and threads are stripped in the process, you could install heli coil inserts, which will dramatically strengthen the block's holding power, but that would require removing the heads. Good Luck!

Fascinating indeed. I suspect the spec. on the reactor stud preload was more likely in pounds rather than foot-pounds, since they were being stretched rather than the nuts being used to tighten to preload. The result is equivalent to using the turns method. In another application, my objective was to preload 4 rods to 50 tons each. I didn't have the resources of a power company at my disposal, so I used a torque mulltiplier on the the 3.5 inch nuts and a five ton overhead crane to pull the end of its bar.

Thanks for setting my mind at ease.

Hi Steve, I just did some quick calculations. The increase in bolt stress due to 1/4 turn on top of the stress caused by your initial torque, as a function of screw length would be as follows: Length Stress, psi 1 453,000 2 227,000 3 151,000 4 113,000 For the shorter screws, these stresses are far too high. Even at 3 inches, even the highest strength bolts would be questionable.

That's an interesting combination of torque and turns I have not heard of before. Were all the bolts the same length? If not, the 1/4 turn would result in quite different preloads.

Quick question: you said "most of the V11 variants". Need I be concerned on my 2004 Cafe Sport?

That's a very thorough approach, and reflects the substantial effect thread and bearing surface friction has on the results of using the torque method. For long studs, bolts, and screws, the "turns" method is more reliable and accurate, but that doesn't work on short fasteners because the number of turns to reach 50 to 75% of yield becomes a matter of too few degrees to easily measure. For example on 4 foot long threaded rods, it takes in the area of 1.5 to 3 turns beyond "snug", depending on the amount of preload required. The rod is being stretched a defined amount as a spring, taking advantage of the relatively reliable spring constant of the alloy. In this case, the lubrication of the threads and bearing surfaces only affects the ease of obtaining the number of turns required. For example, it took about 3,000 foot pounds to tighten the nut on a 1.25" rod to the 1.75 required turns in a particular job I was doing. As long as the threads were free to move, lubrication was not critical, although we were careful about that anyway. We had three strong men hang on the end of a 10 foot pipe on a breaker bar, and then jump up and down to get the job done. In the case of short fasteners, the basis for the torque spec. is the ratio of tension generated to torque determined by the thread pitch and diameter of the thread. It's analogous to driving a wedge. Any variation in friction affects the accuracy of the preload. Hardened washers with smooth surfaces are important for highly stressed fasteners. If the washers are too soft and gall during tightening, you can imagine how much that will increase the friction. On large diameter, short screws where we need high preloads, when necessary, we will preheat the screws and torque them in as fast as practical. They contract as they cool down to get the preolad we need. Thirty years later, when attempted to rebuild a machine done this way, removing a fastener like this can be a real battle. An item not mentioned in the article is the class of thread. It's amazing how complex the specifications are on fasteners for highly stressed applications, for good reason.

Ratchethack, Of course, you're concern about the variable is well taken. My measurements were carefully taken under the following conditions: Filter changed, bike held level via overhead crane, sump drained overnight, filter cover wiped dry, vernier caliper to obtain location of dipstick relative to block gasket while dipstick was screwed in, tri square to verify dipstick angle was 45 degrees, 70 degree ambient temperature, and oil volume accurate to + - 1/4 ounce. I feel that measuring oil level with the dipstick resting on the threads is less accurate, particularly due to the challenge of trying to maintain the dipstick in line with the threads, and not allowing it to droop down into the oil. The manual does not specifically state whether the 3.5 liters includes filling the oil cooler and other parts of the engine. I supposed it was reasonable to assume they intend 3.5 liters under refill conditions. I was content with my 0.69" location also because that was still 1/3" below the gasket. In the case of at least my bike, and probably most, if not all with the broad sump, it appears volume measurements were more accurate than the dipstick marks for the purpose of calibrating the dipstick. Of course, having done that, henceforth I'll be using my new marks so I won't have to bother with the painstaking steps described in my first paragraph.

On my bike, with the dipstick screwed in, the oil level at 3.5 liters is 0.69 above the full mark. At the bottom of the plate, the level is a full inch above the full mark!

Gary, personally, I'm very interested in any objective data you may obtain, and would consider your sharing of that info. a generous act. I share your interest in experimentation. At Tymac, we make 2000+ horsepower hydraulic metal injection systems for pressure die casting. Surge tanks (accumulators) are used to maintain oil pressures of 2,000 to 6,000 psi at flow rates of 2,000 gallons per minute, so I have some experience with their design and application. I'm intrigued about using one on a bike, but have two comments: One concern would be how much additional oil would be needed. The other is that unless some additional sequence valving were used, the surge tank would consume some oil during cold starts that would otherwise go to the engine, as pressure builds in the surge tank.

Thanks, Pete. I understand completely. I'm a mechanical/hydraulic/electronic engineer and have a fairly thorough knowledge of theory and hands-on practice regardling motors. It's the details and seeking perfection in the physics and the operation of my vehicles that interest me. FWIW, in another thread on the oil filter cover, I had reported measurements of oil level vs. dipstick marking, and noted that on my bike the full mark was 0.69" low at 3.5 liters. Actual oil level was 1/3" below the block/sump gasket. That's pretty close to your recommendation, which I agree with. I'm still learning about my V11, and your comment about pressurization caught my eye. Surely there must be some method of balancing the internal pressure to atmospheric. I don't recall whether the pistons are 180 degrees out of phase. If not, pressure amplitude would be relatively higher, and increase with more oil in the sump, but not the average pressure, it seems to me. On the other hand, my Norton was equipped with a very low cracking pressure non-return (check) valve on the breather hose, intended to create a partial vacuum in the sump to reduce oil leakage. Perhaps the same system is used on the V11?

On the positive side, did you learn anything regarding what method the technician used or did wrong?

I'm having trouble seeing how the oil will be prevented from seeking the same level as before under hard acceleration, because of the presence of the large rectangular hole which is towards the rear of the sump, as I understand it. I can't imagine it will take more than a second for the oil to flow through that hole. Does anyone have any data on rates of acceleration, or something like 0 to 60 times? With that information, the angle of the oil surface at the maximum rate of acceleration could be calculated and some estimate made of at what point the theoretical oil surface falls below the pickup. Having said that, if nothing else, the sloppage plate should reduce the tendency for sloshing back and forth under jerk conditions. ("jerk" as in the scientific term, not as a commentary on the character of any of my fine colleagues!) Of course, a super wheelie over a long enough distance would probably starve the pickup for oil no matter what type of sloppage plate were installed, short of fully sealing the sump with some creative method of getting drain oil back into it. That's an argument for dry sump lubrication. I never worried about it with my Norton. I'm looking forward to reading the results of the test.

This old timer agrees with all you say. When I rebuilt engines in years past, it was easy to take out the distributor and spin the pump with an electric drill, followed by your method of cranking. With my boat, which had carbs and pressure guages, I would crank it to build pressure first, because it would never start cold unless the accelerator pump was goosed and clutch allow to close. It used to take a good 10-20 seconds to build up oil pressure. The anti drain back valves in some filters help, and the one spec'd for my Guzzi has one. However, since the filter is mounted upside down anyway, I wonder if that does anything but add a little pressure loss. In the "good old days", my 1967 Barracuda's 383 high performance engine came with a windage tray. I think it was primarily for keeping the oil away from the crank, since it had holes near the rear of the engine which would do little for preventing pump starvation. Acceleration was pretty good, at zero to sixty in 6 seconds, yet I never had a problem with oil starvation, so I suppose the sump and pickup design did their job.

Isn't scraping the pavement simply a matter of the angle between all parts of the bike and the road? Low can be all right, if it's closer to the centerline of the bike. It all depends.

Cool! I have been attacking my stock Cafe Sport mufflers with a Dremel tool, but still am unhappy with the sound, and don't want to perform major surgery. I loved the sound of the reverse cone standard mufflers on my Norton, and they are far less expensive than the aftermarkets I've seen for the Guzzi. However, the diameter of the exhaust pipe end is too small for direct connection. I'll be watching your progress.

See also other threads on Sloppage sheets for details and also on oil filter cover and other threads concerning inaccurate dipstick full marks. My '04 Cafe Sport's full mark is 0.69 inches below actual, when screwed in as my manual instructs. If I went by that, I'd always have far too little in the sump, much worse if I let it go down to the low mark. I'm making my own marks When filled with 3.5 liters as the same manual specifies, oil level is still safely .33 inches below the sump to block gasket, where the Sloppage sheet is intended to go.

On the filter supplied with my bike, it specified 10-12 N-m. However, this is far less than the torque required when I use my favored turns counting approach even with the gasket oiled. Like Rachethack, I too have never had a filter come loose. I have changed the filters on all my family's vehicles for over 35 years, and never had one come loose or leak.