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Allan Edie

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  • Gender
    Male
  • Location
    British Columbia Canada
  • Occupation
    Retired
  • Boat Name
    Friday Girl
  • Boat Location
    Prince Rupert, Rushbrooke Marina

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  1. Interesting experience. Presumably pretty much the same as the Bon Ami cure, which works by introducing a mild abrasive into the engine to abrade the cylinder walls and piston rings to get the rings seated. The main difference (at least hypothetically) between introducing the abrasive in the oil, which worked for you, and introducing Bon Ami into the intake air stream, is that, arguably, less of the Bon Ami would make its way into the oil and thereby to the engine bearings and camshaft train. I considered the Bon Ami cure when my rings failed to seat for the second time, but decided against it because my machinist advised that if I put the stuff in there, I would never manage to get all of it out. On the other hand, the tech at Finning said little or none would actually get into the oil - he also confirmed from personal experience that Cat used (and may have developed the process in the first place) the Bon Ami treatment when they had repeated difficulty getting a particular combination of keystone rings and cylinder liners to seat some years ago. It also occurred to me that the mild abrasive might quickly break down into such fine particles that any residues after the first couple oil changes might be trivial. This seems consistent with both your experience and that of the Cat people. Anyway, in the end, since I had the time, and the cost for a new set of rings and a few gaskets was not that bad, I just re-honed and re-ringed. Bon Ami might have worked, but I decided not to risk it. Cheers, Allan Edie
  2. Yes, I suspect that the cost of my rebuild would have been a lot higher if I had done less of the work involved. Getting the engine from the boat to the shop and back was a project, as of course was the removal and re-installation, never mind pulling the thing twice while chasing the oil consumption issue. If I had paid to have all that done, and had I paid full current price for all the parts, I doubt that the rebuild would have made economic sense. Had I to make the decision again, and if I did not have a few thousand dollars worth of rebuild parts and spares in hand, I would just install a Kubota. As far as I can tell from the pictures and specs, the equivalent Kubota would be a drop in replacement if custom engine mounts were used. I came really close after summer #2... As for the initial ring seating, there is mollycoddled, and then there is near full throttle for three hours without even warming the engine up. Neither of my two initial attempts would have been considered shy, but at least the second attempt absolutely failed to seat the rings, and the first attempt was likely marginal. Were it not for running into the information about the process used by shops with dynamometers, I would never have imagined that I would have to hit the engine that hard initially. I don't know whether this heavy an initial load is appropriate for a more normal honing end point rather than a ball honed cylinder already polished by previous running, but it seems that it has finally solved my oil burning issue, for which I am very grateful. If I had to pull that engine for a fourth time, I am not sure it would be going back in again.
  3. Yes to both Tony. The lower end was completely disassembled, the block bath cleaned etc. Also, the camshaft, timing gears, timing chain, and the rest of the valve train from cam bearings (new) to valve seats (new) was all replaced new. The skew gears looked good as new to me. I am not the original owner, but as far as I can tell from the records, previous owners took very good care of the engine. It still had traces of cross hatch marks after over 7000 hours, and worked flawlessly. I would not have bothered with the rebuild yet if the opportunity to have the machining work done locally was not about to disappear.
  4. Sorry guys, I couldn't figure out what the problem is, so here is the text: To rebuild or repower was the question. The BMC 1.5 in our sailboat still worked perfectly, but with 7000 hours on it, it was time to consider options. Because I had stockpiled some high quality parts in anticipation of a rebuild, and because the only local engine rebuilder was about to retire, I decided to do a preemptive overhaul while he was still available. I stripped, pulled and delivered the engine to the rebuilder myself. An interesting project that, but relevant here only in that my costs were less than many owners might experience for the same level of work. Some $4500 or so and several months later I re-installed the engine, it started instantly on the first try, and I was pleased. During ~200 engine hours in the first summer season, the engine worked perfectly. However, it consumed ~1.5 liters of oil/100 hours. Not acceptable as far as I was concerned, not too bad according to the rebuilder. I attempted to reduce oil consumption by upgrading valve seals and altering crankcase ventilation - neither made any difference. I concluded that the problem had to be rings - perhaps compression rings put upside down. The OEM scraper rings I supplied with the new pistons were not marked, so I was suspicious. In the end, having exhausted other options, I bought a used engine stand, adapted it to bolt onto the engine bed on the boat (wouldn't want it getting loose during rough weather at the dock), pulled the engine and pulled it apart to check the rings. All rings had been installed right side up, and as far as I could tell from wear patterns, they had seated ok, although the oil rings not perfectly. However, the ring gaps were dramatically larger than specs. - ~200 - 300% of minimum spec on most of the rings. In the rebuilder's defense, I supplied the rings with the new pistons, and by the time the rings needed to be fitted, the engine was long overdue to get out of his shop. The last thing he wanted at that point was for the thing to sit there for another month while I got into another frustrating interaction with a supplier. In any case, all considered, I figured that the oil consumption problem was likely due to excessive blowby due to oversize ring gaps, possibly exacerbated by incomplete seating of at least the oil rings, if not the compression rings as well. So, after ball honing the cylinders, I replaced the rings with a new set, perfectly gapped, and put the engine back in place. The following season, over another 200 or so hours, the engine worked flawlessly, but the oil consumption was, if anything, worse than it was the first time. I was not well pleased. The engine went back on the engine stand at the end of the summer season. I found that the rings, the second time around, had not seated properly - both compression and oil rings showed inconsistent and incomplete wear patterns on the sealing surfaces. After much head scratching and digging for information, I concluded that I must have been insufficiently aggressive with the ball honing, or with the initial workout I gave the engine, or both. On to round 3. Again, I installed yet another new set of rings, perfectly gapped, again after ball honing, only this time ~50 strokes instead of 20. I also replaced the standard top oil ring with a modern three piece ring instead of the older single piece cast ring. When I first started the engine, as soon as I knew that I had oil pressure and cooling, I took the engine to ~2500 rpm in gear while moored at the dock. I figured this to be ~75% of full power output which is what I understood to be the approach used by at least one rebuild shop which uses a dynamometer during initial ring seating. It now finally appears that oil consumption is very low, undetectable after ~20 hours of running subsequent to the initial 3 hours of ring seating. About time. My conclusions here are: 1. Good luck finding a shop that actually does a rebuild properly. The fellow that did my rebuild had many decades of experience, did all his own work personally, and came very highly recommended by a car rebuild enthusiast whose opinion I trusted. When I pulled the engine to check his work, the cylinders were as perfect as I could measure using professional tools, but the ring gaps were grossly outside specs, presumably because he did not check the gaps, or because he did not want to delay the work to obtain a new set, or because he did not consider the over large gaps to be a problem, or perhaps more than one of these. In any case, in spite of my best efforts in choosing a shop, the rings were installed grossly out of spec, and I suspect that that was a large contributor to my initial oil consumption problem. 2. The initial load on the freshly rebuilt engine needs to be serious right from the initial start. The failure of my second ring installation was almost certainly due to my not being aggressive enough. I warmed up the engine under low load before ramping up power over the next several hours of operation. The third attempt did the job by immediately (i.e. within less than one minute) taking the engine to ~2500 rpm, in gear, tied to the dock, which I figured was something like 75% of maximum power in my installation. In retrospect, I doubt that my first attempt was anywhere near aggressive enough either, although the seating seemed to be noticeably better the first time around. However, the two honing jobs were dramatically different - the first starting with coarse stones to remove the ridge at the top of piston travel, the second being ball honing only after the cylinders had been polished by the initial seating attempt. Apples and oranges as far as the microscopic cylinder surface is concerned. 3. Although I will never know what the exact contribution of the new three piece rings was relative to the more aggressive ring seating during my last attempt, I think that replacing the top cast oil ring with a modern three piece ring is a good idea. The modern design was available for the grooves in the OEM pistons I used, and presumably would be for aftermarket alternatives. The newer ring design controls oil better. The older cast rings do not conform to cylinder walls as well as the modern 3 piecers do, and they apply less pressure, less consistently around their periphery than the new ones do. Thanks here to Dawn at Hastings Rings for patiently investigating options and advising me on their experience with rebuilds like mine. Had I to do it all over again, I might choose a new Kubota instead of the rebuild. The repower would have been less work, hassle, and frustration. On the other hand, I now have the job done, my costs were less than half that of a repower, and I really like the BMC 1.5 installation. In the end, I don't regret the decision to rebuild, but I wish good luck to those faced with this dilemma.
  5. I have recently finished a rebuild saga that owners of BMC 1.5 might be interested in, especially if they are considering a rebuild. The experience is documented in a blog at: https://www.blogger.com/blogger.g?blogID=5669388339113821275#editor/target=post;postID=4460763766630206706;onPublishedMenu=allposts;onClosedMenu=allposts;postNum=0;src=postname Enjoy, Cheers, Allan Edie
  6. Hi, I dealt with a leak on this housing, and it turned out not to be any of the rubber seals at all, it was the joint between the housing body and the insert into which the idle damper screw is threaded. This insert, believe it or not, is glued into the housing, and the joint can and will fail sometimes. You should make sure that this joint is not your problem before assuming that the rubber seals are the issue. The cure in my case was to pull the housing off (already done by you), pull the damper screw out of the housing (if you note very carefully exactly how many turns it takes to disengage from the threads, you will be able to set it at the same damping setting when you re-assemble), pull the trottle/stop assembly out of the housing. Having done all this, you will have the bare housing with no rubber seals still inside anywhere. At this point, my insert pressed out of the housing with minimal resistance. You may need heat to help soften what glue is left in the joint. Once the insert is out of the housing, clean the joint surfaces off carefully and thoroughly, and re-epoxy. Doing the epoxy reset has to be done carefully to ensure that the joint gets filled with epoxy and stays that way. I accomplished this by first off taping the inside of the housing at the lower end of the insert skirt on the inside of the housing so that excess epoxy can't get up to any mischief. Then I applied a moderately generous layer on both the insert surface and the housing surface before inserting the insert into the housing. This will cause excess to peel off both outside and inside., and ensure that air pockets or glue starvation does not happen. Twist gently on the way in, and once seated, do not disturb. I held the insert in place by squeezing gently to lock it in place while I cleaned up the excess both outside and inside. Let the epoxy harden before doing anything further, then remove the tape and make sure that no excess got up to mischief inside. On my job, I thickened the epoxy with fumed silica somewhat before using it. I also, once the epoxy inside the joint was set, applied a thicker mix of epoxy, silica, and ground glass fiber to the top of the joint on the shoulder where the insert sits on top of the housing. The pump has now been run for about forty hours, and it is absolutely dry. As an aside, I also found that the housing into which the fuel return pipe threads was also leaking, and I solved that by applying an epoxy collar around the leaking joint, tapering it to the surface of the threaded insert and to the surface it is pressed into. Again, after about 40 hours, the pump is now absolutely dry. Just my experience for what it is worth... Cheers, Allan Edie
  7. On holiday and still monitoring this site to help out - a rare fellow I would say. Thanks for the manual, I had a look at it and agree that there is nothing shown that should get up to mischief, so I will pull the damper screw and lock nut to see what I can find out. Thanks again for your help Tony, I will let you know how I make out. Cheers, Allan Edie
  8. Thanks Tony, I will pull the damper screw and lock nut when I am out to the boat next week. Can I assume from your comments that the damper screw can be fully removed without running into difficulty getting it back in correctly, i.e. no springs to launch across the engine room, or micro parts to fall out of place somewhere? I'll measure the position so that I get it back into more or less the same dampening position to make adjustment easier. Absent contrary instruction from you, I will loosen the lock nut, then back the damper screw out completely so that I can check the sealing washer setup before putting it back together. I'll make sure that the sealing surfaces are ok, and consider whether another washer would help. I suspect that the issue is the seal that the washer provides around the actual damper screw threads, not the seal between the lock nut and the body of the throttle assembly, so a dowty that fits might solve the problem if the washer in there now can't do the job. My likelihood of finding one in Prince Rupert is likely zero however, but I can order on online for the next round if needed. Thanks again for your help Tony, I appreciate it. Cheers, Allan Edie
  9. Hi Tony, I forgot to mention, my engine is the 1.5, not the 1.8. I am sure that the leak is not coming from the glue seam, I have run into that problem some time ago. I have also dealt with a broken off bleed screw that the previous owner left for me. The diesel is definitely coming from above the glue joint, most likely from the damper screw threads where they meet the top of the lock nut. I need to know whether the design of the assembly is intended for torque on the so called lock nut to apply pressure to the sealing washer, thereby squeezing against and sealing the damper adjustment screw threads. If that is how the thing works, I will try tightening the lock nut. If not, one option would be to pull the pump and send it back, but that would be inconvenient due to the boat being in one place, me living in another, and the re-builder somewhere else. If the problem is a failed sealing washer or some other issue that simply needs a part, I would prefer to have it sent to me and for me to put it in myself. Alternately, perhaps I could remove the entire damping assembly and send it back for repair. Any thoughts on those alternatives? Thanks for your prompt reply Tony, you are a very generous with your support of this forum, and many of us are very grateful it. Cheers, Allan
  10. Hi all, New here, but long time BMC owner. Recently rebuilt cav injection pump is leaking at the idle damper screw. The leak seems not to be the bleed screw, which stays dry. As far as I can tell, the leak is from the idle damper screw threads. My question is whether the lowest nut into which the damper adjustment screw threads, I believe it is referred to as a lock nut, the one that has a sealing washer under it according to the diagrams, should seal these threads if I tighten it more than it currently is. Is the normal adjustment sequence to loosen this lock nut prior to changing the damper screw setting? Perhaps the rebuilder did not tighten it because he anticipated that it would need adjustment once replaced on the engine. Thanks for the help, Cheers, Allan
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