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I rebuilt the B18 in my 65' 1800 last year and after doing all the proper break in stuff, correct cam lube on cam lobes and lifters. Using RP break in oil. Running for thirty minutes between 2-3 thousand RPM. Changed the oil and filter right after, used more RP break in oil for the next 1300 miles, then at the beginning of this spring changing the oil to RP HPS oil which has higher levels of phosphorous and zinc for flat tappet/performance engines. After all that i have a severe failure on the number three valve, after adjusting the valves numerous times because the valve train seemed to get "noisy" i finally checked all the clearances before re adjusting, sure enough just one valve did not hold its adjustment, the clearance grew .010" in just under fifty miles! My magnetic drain plug also shows the telltale metallic paste of bad wear. I will be pulling the head to investigate but was wondering what happened? Also if i find the lifter bore is fine and the cam measures lift correctly can i just replace the one bad lifter? The lifters all spun fine in their bores when i installed them and everything is new. Stock "C" grind with stock type lifters and pushrods all new from VP autoparts. Any help or advice is highly appreciated.
Thanks!
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I pulled the head and have found the source of the wear. It is not anything on the camshaft or the bottom face of the lifter. Rather the top socket on the lifter on #3 valve has been severely eaten away by the pushrod. I measured it and it is .020-.022 shorter than the others because of the excess wear. I checked all the cam lobes and they all measure out with the correct lift and visually look good as well. Bottom of all the lifters all look good as well. Oil supply holes all are clear on the rocker shaft and the rockers and valve tips look good. So i strongly believe the lifters supplied with my VP cam are defective junk, the pushrods also came from VP and are undamaged. So the lifters maybe are too soft, or pushrods too hard? The other lifters showed some decent wear from the pushrods as well considering they only have 1,500 miles on them. So i am putting in a set of Isky SBC style lifters and their matching pushrods and breaking in again. I see no reason to do a cam change at this point. I have contacted VP and am hoping they can help offset the cost of the new parts, gaskets and break in goodies.
Thanks for all the help!
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What lube did you use on the pushrod ends?
You will be a very lucky man to have the cam survive a 2nd set of lifters, since it's already bedded in to the 1st set of lifters.
Since the cam lost no lobes, best choice is to have it reground using a better profile over the current lobe centres. K or VV-61 ground on the C lobes would make good cam.
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An alternative falsehood is an alternative fact in a post truth world. - TG.
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I used compcams break in lube on all push-rod ends, lifters, rocker tips, etc. Everyone i talk to says putting new lifters on a used and undamaged cam is no problem. Both VP and a rep at Isky said it should be no problem either. A new cam with used lifters is a very bad idea though, not that i would ever attempt that. Again i only have 1,500 miles on the cam using proper break in lube and the lifter bottoms show no unusual wear patterns. The wear was the push-rod into the top of the lifter, possibly because of a hardening defect or mismatched radius between the lifter socket and push-rod tip.
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I'm not going to argue with a cam company, so I wish you good luck!
.
If it were me, I might have risked trying replacing just the one lifter, since you know the other 7 are perfect. In the past when I have knocked a lobe off a race cam, I've had the lobe welded (or rewelded), just the one lobe reground and replaced the lifter.
BTW, which lobe was it and why did you go with such an ancient cam?
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Again the lobe is fine, the top of the lifter was eaten by the pushrod. Number three valve. I am changing to the sbc lifter and longer pushrods so doing just one is not an option. I would have/should have gone with an isky grind cam but I simply built my B18B to mostly factory spec because i just wanted it to work well for a long time. If anything gets damaged again it will be getting a VV61 with new lifters for sure.
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I've changed or helped change cams 100+ times, not all B20's, but from as small as a BMC-A to as large as an EMD 645. Isky fell out of favour with me in the early 1990's due to a drop in quality and I can tell you that: In B18 and B20 flat tappet cam and lifters are both made from the same cast iron and hardened to 55RC, the lobe and lifter bed in together after which you should not mix them up. Usually you can move a healthy cam and lifters from one block to another, but sometimes that will end in tears too because the lifter bores can vary in their location. So this is why I wish you good luck.
The Isky and any other rep have one job, to sell you stuff. Isky have no stock cams I can recommend, VV-61 is ground on the wrong LSA, it would be a very close match to Volvo's K cam if you had it ground on 111°. Generally single pattern cams are not exactly right because all of Volvo's 2 valve gasoline motors have woefully inadequate exhaust ports. For all B18 and B20 engines with stock heads and valve springs I always recommend the K because it is gentle while being upgrade in performance to an A or B cam when timed in correctly, and upgrade in performane and economy to a C cam. The D cam was designed in the 60's for the B18B powered Amazon rallycars, the D cam with dual springs, but they cheaped out when the used again in the B20E and stayed with single springs. The K will beat a D cam up to 5000rpm and is 5hp behind at 6000, but when the stock springs have a few miles on them, they will lose control of valvetrain when they hit their harmonic at 5500.
So, keep us up to speed on how it goes.
Also, was the old cam a CWC core? Does the VP cam have a CWC core? What was wrong with the original pushrods?
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I should also mention that B18's can sometimes have a poorly located or angled lifter bore, which lobe was worst on the original cam?
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An alternative falsehood is an alternative fact in a post truth world. - TG.
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Does the core of the cam have CWC MADE IN THE USA on it?
You did it fairly corectly, I cycle between 2000 and 2500rpm, but I doubt 3000 would have hurt.
It would have failed during the 1st 20 minutes, while the first lot of oil is draining, I bar the engine around and watch each lobe go through full lift, failed lobes are visually obvious 95% of the time. Also note that 4 lifters spin in the opposite direction, when you look down the lifter bores at the lobes, 4 are offset fowards of centre of the lobe and 4 rearwards. Some grinders don't know or are too lazy to change the lobe taper on the grinder.
Next cam, get a K and dial it in 4°-5° advanced.
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An alternative falsehood is an alternative fact in a post truth world. - TG.
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Now you have peaked my curiosity. On an engine with a cam belt / chain with offset mounting bolts for the cogwheel / sprocket you can have a vernier style adjustment in the cam timing. How do you do that on a gear driven cam where the gears on the crankshaft and camshaft are fixed by woodruff keys? Your ability to adjust timing is based on the fixed increments associated with the tooth spacing (unless you are prepared to dispense with the woodruff key?).
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http://www.tinustuning.nl/1-onderdelen-nokkenassen.html
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An alternative falsehood is an alternative fact in a post truth world. - TG.
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On an engine with a cam belt / chain with offset mounting bolts for the cogwheel / sprocket you can have a vernier style adjustment in the cam timing. How do you do that on a gear driven cam where the gears on the crankshaft and camshaft are fixed by woodruff keys?
That's the way to go on the OHC donks when you have tonnes of cash! If I had a B23 or similar, it would be the last place to spend money.
The old fashioned way is to make or buy an offset key for the cam, for a few dollars more, you can get the crank gear cut with offset keyways, which is typical with aftermarket timing sets for pushrod V8's. I've seen offset cam keys on the www, I'd start with Tinustuning.nl
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An alternative falsehood is an alternative fact in a post truth world. - TG.
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Was the cam you put in it NOS? A few years ago my son bought a '72 with about 40K on it but the stock cam was wiped on more than one lobe. I think Volvo made a few improperly hardened cams back then. We replaced cam and lifters and it ran well for many years.
I think you're going to have to replace the cam and AII the lifters to be safe.
Tom
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The cam and everything else was purchased new from VP. I am likely going to have to pull the cam and replace all of it. With that i am tempted to go with an aftermarket cam and lifters since i am now a little distrustful of the stock pieces. I was considering one of the two isky profiles that IPD sells.
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It sounds like you did everything right during break in and then some.
Did you use VP's performance lifters or their stock lifters?
I have only sold 1 VP camshaft and that was for a 6 cylinder and AFAIK it is still okay as the customer hasn't let me know otherwise in over a year.
Camshafts for Volvo's pushrod engines have been a problem for a long time.
I used to be able to get high quality aftermarket camshafts made by TRW in Europe and they also made high quality valves and valve springs for the B18/B20/B30 engines. But that all came to end when Federal-Mogul bought TRW's automotive division and shut down the plant that made the valvetrain parts. I have always assumed they shut it down because they already owned SealedPower which makes valvetrain parts, BUT NOT FOR PUSHROD VOLVO ENGINES.
So we got to experience the wonderful world of whitebox no-name camshafts which ended after I found the piece of crap I installed in my own stock engine wasn't ground correctly. I was setting the valves and noticed that I had more lash on both #4 valves after I had adjusted them while adjusting different valves. When checked, the timing was off so that #4 valves were opening/closing sooner than they were supposed to.
So onto Volvo OE camshafts.
Volvo did have their own camshaft problem and they had to replace a large number of camshafts. Since then, the camshafts are high quality, but have gotten ridiculously expensive and by the time we took action, the camshafts cost over $300.00 and now cost over $1000.00.
So I have high quality copies of the "D" camshaft made.
FYI, I also sell Isky's camshafts as well as my custom made "D" camshafts for $200.00 each.
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Eric
Hi Performance Automotive Service (formerly OVO or Old Volvos Only)
Torrance, CA 90502
hiperformanceautoservice.com or oldvolvosonly.com
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Did TRW buy CWC?
CWC MADE IN THE USA cast on the core become the only manufacturer of good blanks for decades, started appearing in 1973 motors and became the sole manufactuer for flat tappet castings for all makes.
Does your genuine D cam have .281"/.282" lobe lift and is dual pattern? I would not use one without dual springs, the stock springs don't work properly with new stock singles and is the reason a healthy B18B will topend a B20E in P1800 and especially 140's
K cam actually works with stock springs and will beat an A or C cam in any engine and better than the D most of the time. KG Trimning sold K cams for stock B30's and it is the cam in the GT kit that beats a B20E buy a long way.
The reason the early cams failed was the lobes were too wide and poorly located, sometimes causing lifters to spin the wrong way.
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An alternative falsehood is an alternative fact in a post truth world. - TG.
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