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MG TD TF 1500 - Front cam bearing and more
| After having my crank and rods magnafluxed and checking out ok I am ready to bring the rest of the motor to my machinist. I have read many threads in the archives about the front cam bearing. Some state that the bearing didn't need to be honed. Others had trouble with fit in the block. Most posts are somewhat dated. Has anyone here "recently" purchased and installed this bearing? One thread from 2010 stated that most of the bearings fit and need no honing but "an older bearing shows up in the stock from time to time" Also, is there a difference in part quality from one supplier to the next? Pistons/rings, main and rod bearings, cam bearings, valves, etc. Can I assume a gasket is a gasket? Mark |
| Mark Butler |
| They still usually need fitting to your cam. As for quality, it all depends. Some are indeed better than others, some are pretty good, some are good enough - barely - and some are not. No easy answer. Also, ever rebuilder has a favorite source/maker/type of item. A lot of good quality older parts can be found on eBay - I just bought an NOS set of +.040 TF1500 rings for $2.51, plus $5 postage. In general, Moss's stuff is made in Israel or China, usually Country brand. Good enough, I would say, but for a more highly-stressed engine I would buy better quality things. What are you looking for? What size bore? What size valves? Can you see that there is no easy answer? Tom Lange MGT Repair |
| t lange |
| I'm struggling with the front cam bearing in my TF1500 engine right now. Purchased a set of cam bearings from Abingdon and came up with the one with the 45 degree split (see Moss note on cam bearing set problem). The M/S gave up on this one after attempting to file the 45 degree joint as Moss recommends: the bearing wouldn't stop bulging at the split, despite the use of a specially made mandrel. Before I was aware of the plan, the M/S ordered another (from a Brit part supplier in Oregon of all places) and it had the 90 degree split interface but still "bulged" at the split when installed. I'm trying to make this one work by using a bearing scraper and blueing to eliminate the high area. VERY time-consuming but I'm getting there. The block bore measurement was right on the nominal size specified in the manual). Both parts made by "County" in the UK. In my view this is a poor original design which is difficult to manufacture to the tolerances required and is being made an indifferent supplier. Maybe the Moss parts are ok? (I believe they are supplied by County also). Bon chance as we say here in La Belle Province |
| T W Moore |
| TW, Are you sure that "COUNTY" parts are made in the UK???? Sold throught Empire British? SPW |
| STEVE WINCZE |
| Steve Good question. Just an assumption on my part, quite possibly wrong (I WAS wrong once before,in 1972). T Lange says many Moss parts are sourced from China from "Country" brand (see 2nd post above). County or Country? As an ex-manufacturing engineer, I believe the bearing would be much cheaper and easier to make from a steel tube plated on the ID (without the split). Is (was) there a special factory piloted reamer to use when installing the cam bearings? Don't believe there is any mention of this in the literature. |
| T W Moore |
| Sorry - yes, County, not Country. Since loose cam bearings are a major source of low oil pressure, a nice snug fit is desirable, so the bearing is left oversize hen manufactured. I have never seen a factory front cam bearing reamer. Machine shops that have trouble sizing the front bearing usually don't have a reamer that can be supported and aligned by the rear and center cam bearings I also uswed to laboriously scrape, but it always felt hit-or-miss, since there was n alignment with the other bearings. I have recently machined a cutting groove in a bad cam and use it with an old cam gear as a handle, with plenty of cutting oil. It seems to work fine, and leaves a nice, smooth surface. I don't recommend honing, as I think it tends to close up the pores of the bearing. Tom Lange MGT Repair |
| t lange |
| Wow - what abysmal typing. Four typos. Sorry, folks. As people have pointed out lately, I am getting on in years. Tom |
| t lange |
| Hello Tom Do you happen to have a picture of the cutting grove you machined in that old cam, sounds like a very workable solution. Thanks Hiram |
| Hiram Kelley |
| Yes, there is a factory cam bearing reamer. I use one when I install my bearings. You need to ream them to size to achieve proper clearance, for correct oil pressure and flow. If your bearing fits and has proper clearance without reaming, then you're just plain lucky. |
| Steve S |
| The front camshaft bearing reamer 18G351 is shown on page Q6 of the WSM. Also identified there as 8G351. Probably a typo. Cheers. Peter TD 5801 |
| P Hehir |
| Tom Lange Along with Steve, I'd also like to see a photo, dimensioned sketch, or description of the cutting groove in the old cam. (Typos don't bother me). Tom Moore |
| T W Moore |
| I lent the cutting cam out to friends who are using it, but as soon as it returns I will photograph it. Tom Lange MGT Repair |
| t lange |
| Correction: as noted, there is a factory front cam bearing reaming tool in the manual(p Q6,p/n 18G351) AND the manual does say that reaming is required when fitting a new front cam bearing (p A17). Note to self: READ THE MANUAL! Neither the Schach or Malcom Green books mention the reaming operation. |
| T W Moore |
Here you go, factory reamer in use. Sorry, it's the best photo I have at the moment.
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| Steve S |
Here's the one that I had made from a camshaft with very worn lobes. The journals are hardly worn. It's worked like a charm for reaming the front bearing after knocking it in place. The cutting edge is very sharp. Bud
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| Bud Krueger |
| In an effort to track down the Brown and Gammon (ala C.T. Irwin) type front cam bearing I managed to find it at British Parts Northwest. This cam has the "puzzle piece" seam. I inquired who produces the bearing to be sure it was in fact different than the Moss bearing. I also questioned the fit of the bearing. Below is Leightons quick reply: ""They are made by CMPM and we have not had any customer feed back saying they needed to machine any of the front bearings. I just called a local shop which installed a set about three weeks back and they did not have to machine the bearing. And last we are not a Moss reseller we source our own parts. Anything else let us know and have a good week."" Regards, Leighton British Parts Northwest |
| Mark Butler |
| Good morning Mark The front cam bearing I described (that was obtained by the M/S AFTER difficulties with the County part with the 45 degree seam) was from British Parts Northwest after seeing an illustration of the "puzzle piece" seamed bearing on their internet site. The part that arrived was a County bearing identical to the first one but with a 90 degree seam cut. Hopefully "Leighton" at BPNW is basing his comment on current stock because what they delivered was not as he claims. To conclude this long thread, I have been able to get the cam installed satisfactorily but only after many hours of measuring ,scraping, filing, blueing, and honing. If I were doing it again I'd make a reamer from an old cam as suggested by T Lange. Please confirm that the front cam bearing you get from BPNW is the one with the "puzzle piece" seam. Good luck. |
| T W Moore |
| Hi everyone, Over the last 10 years I have fitted at least 5 cam bearing sets and have never had to ream the front bush. Cheers, David |
| David Tinker |
| Thank you Tom. I will update the group when I have more to report. David- what bearings do you use? Who supplies them? What type of seam? |
| Mark Butler |
| Mark, Attached is a pic of the front cam bearing which I use obtained from Brown & Gammons and as you can see it is of the straight split type. They are not easy to insert and is essential to have a close fitting mandrel for the centre bush bore which extends at least to the full length of the bush. The mandrel must be shouldered of course and with a 10mm dia hole through the centre. A close fitting shouldered mandrel is also required to locate in the back of the centre bearing hole also with a 10mm hole through the centre. With a length of 10mm threaded bar inserted through the mandrels with nuts and washers on each end you can draw the bush into place. A close fit between the threaded bar and the mandrel holes are essential to hold everything in line. Finally fit a jubilee clip over the bush to compress it on to the mandrel and with plenty of lubricant carefully wind in the bush. This works for me and I hope it helps others. Cheers, David 
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| David Tinker |
| And to think, 15 years ago I pressed a Moss front cam bearing in my XPAG, reamed it to fit the cam with a brake hone and years later still have 60 psi oil pressure. Gene |
| Gene Gillam |
| Dave Tinker: sounds like a thoughtful approach and not at all difficult to make the tools up. Gene Gillam: Yes but your bearing was probably made by the original supplier, not County's Indian source. One wonders if any installation trials were ever done on the new parts when the source was changed. At $17 each, probably not. |
| T W Moore |
| David, is the locking tab already cut into those bearings? I've always had to knock the tab into the slot. This then distort/eds the bearing at that point and required a degree of reaming. Bud |
| Bud Krueger |
| Hi Bud, The locking tab is not preformed in the bush but I have not experienced any issues resulting in knocking the tab into the slot. In my previous post I forgot to mention that it is critical to ensure that the oil hole in the bush lines up with the oil hole in the block. Cheers, David |
| David Tinker |
| Here is a couple shots I just took of the factory cam bearing reamer. Butch 
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| R Taras |
| Bonsoir Mark Butler Did you receive the cam bearing from Leighton at BPNorthwest with the wavy "puzzle piece" split line? I've got my cam installed satisfactorily but I'm curious if BPN delivered a non-County made item. The M/S that did the work on my engine is still pissed off that BPNorthwest didn't deliver what they promised. |
| T W Moore |
| Through numerous calls to various suppliers, it seems the County bearings are King brand, made in Israel, and pistons are from Taiwan. |
| JRN JIM |
| TW- I just received the bearings yesterday from BPN. The front cam bearing does have the puzzle piece seam. I believe it to be a County part. It was separate from the box containing the middle and rear bearings which were marked County. The part number on the bearing is CSB 8765. The packaging it was in in labeled GS8765. See photo. I will report back if the shop has a problem installing the bearing. I did notice that there is no visible tab that prevents the bearing from spinning. The shop will investigate. Their initial thought is that it's a press fit and will be fine. They state the fact that the old one had to be machined out of the block as evidence. Thoughts? 
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| Mark Butler |
| Hello Mark. There should be a groove machined into the face of the block on the edge of the hole. After installing the bearing you use a punch to bend the edge of the bearing into the slot and lock in place to prevent rotation. After that you can ream to size. Butch |
| R Taras |
| Bonsoir Mark Thanks for tying up the end of this saga. That's exactly what we were led to believe we were getting from BPN but not what showed up. Hard to understand when communication was quite direct. I wonder if Moss and Abingdon will now supply this improved part? Good luck with the installation. |
| T W Moore |
This thread was discussed between 15/03/2014 and 12/04/2014
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