Author Topic: 2.0 Valve adjustment (Read 12056 times)

rramjet · « **on:** August 28, 2013, 03:18:52 PM »

Taking a break after adjusting the valves on my 73 with a 2.0 and 95K miles. Found all of the Exhaust valves were really tight. Probably explains the crappy idle and lousy performance. I've read elsewhere that the valves on these things need regular adjustment but not sure how often that should be. I have no idea when and if they were ever adjusted before. I'll probably be lucky if I don't have any burnt exhaust valves. Helps explain the low compression readings 130 lbs I was getting. I had thought it was because I did not block the throttle open before doing the check. Didn't do a leak down test yet.

Also thinking tight exhaust valves might be a sign that the seats/valves are recessing into the head.

Heading back out to reassemble everything and see what it runs like.

Wittsend · « **Reply #1 on:** August 28, 2013, 04:52:42 PM »

Before I went 2.3 Turbo I had a similar experience with my 2.0. I got the car at 86,000 and after a valve adjustment my compression also improved. I think some of my cylinders were well below 100 lbs and after the adjustment they were in the 125-140 lbs range. Seat recession is about the only thing I can think that would cause lose of clearance. My engine smoked faintly and I'm wondering if exhaust valves getting hot (or the constant blast of leaking exhaust) damaged the seals.

BTW, I found getting the nuts loose for the adjuster to be a real pain. Some were difficult to get a wrench on and rotation was limited. Anyway, I hope your test drive provided good result.

Tom

rramjet · « **Reply #2 on:** August 28, 2013, 05:39:03 PM »

Adjustment made a dramatic improvement. Actually got the vacuum gage in the middle of the green now and the timing is no where near as advanced as it was. I actually timed it with the vacuum gage. Too lazy to pull out the timing light.

I really do believe the exhaust seats/valves are probably receding into the head and I'm guessing if I keep making freeway runs at 70+ they will continue to do so.

I'm contemplating a head rebuild but will see how long the adjustment lasts.

jeremysdad · « **Reply #3 on:** August 28, 2013, 05:49:42 PM »

"Also thinking tight exhaust valves might be a sign that the seats/valves are recessing into the head."

Yes.

"BTW, I found getting the nuts loose for the adjuster to be a real pain. Some were difficult to get a wrench on and rotation was limited. Anyway, I hope your test drive provided good result."

Agree with all of the above. I bought stubby wrenches (from Lowe's, but any stubby should be fine), and haven't had to mess with vice-grips or adjustables again.

Best 15 bucks I think I've ever spent.

Also, Ford spec is, I believe, to adjust every 12k miles. I do mine every 2 oil changes and clean the oil bar (carb cleaner) for sanity's sake.

I set them like I set points on engines with 2 screw points: I.e., I set them just slightly loose, so that tightening the lock nut brings them to spec ( always verify with the feeler gauge, never assume). Personally, I have found trying to hold both wrenches to be damn near impossible, except for when I set them on the bench before reinstalling the head (no intake/carb in the way).

One final note: Chilton's is wrong, they're metric (15mm/19mm). However, they are correct in stating that slightly loose is better than slightly tight. I'll take noise over head-work any day.

OP: By chance did you note the condition of your cam lobes? On a mechanical valve train, they should not be shiney all the way around, there should always be some Parkerization near the base (round) of the lobe. Also, your motor should always sound (lightly) like an old Singer sewing machine.

As always, ymmv, and feel free to correct.

rramjet · « **Reply #4 on:** August 28, 2013, 06:09:45 PM »

I visited Harbor Freight and got a set of Metric crows feet 3/8" drive. The 19mm worked fine to break the lock nut loose. In most cases I could actually turn the adjusting nut by hand but used a small crescent wrench, (adjustable metric), if I couldn't do them by hand.

I found the best way for me to tighten them was to find the exact clearance then back the adjuster off about an 1/8 turn, tighten the lock nut snug by hand while holding the adjusting nut then tighten the lock nut with the wrench. Usually the adjusting nut turned just the right amount but not always so there were many repeats. A PIA job!

I really didn't look carefully at wear on the cam lobes other than to see that they didn't appear flattened but it seemed that the only shinny part was the top of the lobe.

As I said the car runs so much better now but I'm holding my breath to see how long it lasts.

jeremysdad · « **Reply #5 on:** August 28, 2013, 08:39:13 PM »

Quote from: rramjet on August 28, 2013, 06:09:45 PM

I visited Harbor Freight and got a set of Metric crows feet 3/8" drive. The 19mm worked fine to break the lock nut loose. In most cases I could actually turn the adjusting nut by hand but used a small crescent wrench, (adjustable metric), if I couldn't do them by hand.

I found the best way for me to tighten them was to find the exact clearance then back the adjuster off about an 1/8 turn, tighten the lock nut snug by hand while holding the adjusting nut then tighten the lock nut with the wrench. Usually the adjusting nut turned just the right amount but not always so there were many repeats. A PIA job!

I really didn't look carefully at wear on the cam lobes other than to see that they didn't appear flattened but it seemed that the only shinny part was the top of the lobe.

As I said the car runs so much better now but I'm holding my breath to see how long it lasts.

I can tell you from experience...s ave for a valve job.

lol

amc49 · « **Reply #6 on:** August 28, 2013, 11:54:10 PM »

Yep, I went to getting 12,000 miles max highway miles at the last with '74 model head. The exhausts just sink like a b-tch. Run them a bit loose to get a bit longer between settings, and once you set them if you take the engine out and run the crap out of it you will get a small amount of exhaust seal back. The semi-molten condition of exhaust run like that lets the seat material flow a bit to fill carbon dents and pits.

Ain't no way around it, if you want a 2.3 to last in today's fuel climate you have to have hardened exhaust seats. The valves sold now work fine if you can get seats in there and correct. And when done the whole thing needs to be put together long enough to check and adjust the valvetip height so that it stays right with hydraulic lifter guts, otherwise the valve can be held open on a new rebuild. People used to make that mistake all the time back when I was running them to make engines that wouldn't run right at initial startup. The mechanics of the day all pronounced the engine as 'funny' and hard to 'get right' for long life, the only trouble I had was after fuel started dropping lead out, the more they dropped the shorter the heads lasted. If not for that the heads would've been bulletproof.

rramjet · « **Reply #7 on:** August 29, 2013, 12:34:48 AM »

Now to find someone who can do a decent job on a 40 year old head.

I'm not sure I understand the valve tip check. Is it needed because the hardened seats don't necessarily all sit at the same depth or variations in valve stem lengths or???

Wittsend · « **Reply #8 on:** August 29, 2013, 01:03:49 PM »

While this goes back to my Datsun 510 days more than Pinto, I think he is referring to the geometry of the rocker arm and the valve tip. If they get too far out from the intended design the contact point at the valve can be too far off center.

I know on the Datsun motor, in addition to adjusting lash, a cam change potentially required different thickness "lash pads." The pads sat on top of the valve stem (held in place by the retainer). Dykum dye would be put on the rocker contact point and the lash pad. The goal was to have the fulcrum action as close to the center of the tip as possible. Again, just a guess, but I think it is what he meant.

Frankly, I'd just drive the car and enjoy it. Is it a daily driver? If not, the wear/tear will probably be minimal. I have three (running) "collector cars" (albeit, cheap ones). I doubt I get more than a few hundred miles on each every year. Thankfully the "Rat Rod" has made concept over condition acceptable these days. Otherwise I'd go broke.

Tom

rramjet · « **Reply #9 on:** August 29, 2013, 03:40:19 PM »

OK I understand. Maybe replacing the rockers if new valves are needed is something I need to consider.

The car is not a daily driver but I have put about 1200 miles on it since getting it in late June and quite a bit has been freeway. I make an 80 mile roundtrip on the freeway every Friday for another hobbly I have and it's just fun to drive and see expressions on peoples faces.

It had a crappy idle when I bought it but the PO said it needed to be timed. It kept running worse so I finally put a vacuum gage and timing light on it and needed to put a ton of advance in it to get it to idle decent but then it started surging on the freeway. Thought initially the timing belt was off a tooth but set everything on TDC and it was good so checked the valve adjust next and wa la.

It is going to our Winter place in AZ and will stay there from then on as a 2nd car.

Thinking I will get head work done here before it goes down. I know more about places here that can do it.

Pintosopher · « **Reply #10 on:** August 29, 2013, 07:40:20 PM »

Since I have a 2.0 semi race motor in mine ,a word of caution. The center cam bearing is prone to wearing out , especially with a high lift cam or long duration setup . This makes the engine nearly impossible to hold a accurate adjustment for any length of time. Add worn valve guides and it's pointless to attempt a smooth idle adjustment. Unless you replace that setup with a Needle bearing roller cam ($$$) , or at least a higher quality bearing shell for that center tower, you will be adjusting those valves a bunch. This is one of the reasons the 2.3 engines have 4 cam bearing towers, and even when you switch them to solid adjustable rocker arm posts, they will hold an adjustment longer, regardless of Camshaft profile.
My two Horseshoes of advice,
Pintosopher

rramjet · « **Reply #11 on:** August 29, 2013, 09:23:49 PM »

Good info. Thanks.

At this point I don't plan on anything more than a reliable funky get around car so no high lift cams or other performance stuff.

If I feel the need for more performance some day I think I would look at shoving a 5.0 in it.

jeremysdad · « **Reply #12 on:** August 29, 2013, 10:20:51 PM »

If you have your head 'shaved', also have the cam journals 'align honed'. ".006" doesn't sound horrible, til you slide the cam in.

Cam journals in an OHC head...what a bunch of bitches.

amc49 · « **Reply #13 on:** August 29, 2013, 10:44:07 PM »

When seats are cut the valve lengths can then vary, modded even more by any work refacing tips. If the guy is sharp, he keeps a chart of how much the valve had removed to clean up, at 45 degree angle he needs to take half that off tip to keep valve the same but still grinding seat effect on head must come in there too.

Used to be a number Ford gave to check that clearance on 2.3 with hydraulic lifters, collapse lifter and then fit valve in hole with a follower and that clearance then gets measured between cam lobe and follower. It guarantees the working assembly is in the middle of the hydraulic travel of lifter for very long life. If valve now ends up being too long after the machine work the lifter runs out of internal adjustment travel while shrinking in height and holds valve open.

No need on 2.0 or engine with solid lifters.

Pintosopher is right, the middle cam bearing in 2.0 wears like lightning. The 2.3 went to four towers to fix it but they wear pretty quick too, even a stock cam will have a wear step in them at 40,000 miles.

Here we go, I found the number, called 'collapsed lifter gap' in '80 Ford service manual and on 2.3 with hydro lifters, .040"-.050". The clearance puts the lifter seat right about in the middle of its' travel or I'm thinking around .080" total travel there.

'Cam journals in an OHC head...what a bunch of bitches.'

LOL........... ...you should try some hot rod inline four bikes now, them heads are swiss cheese........ .........

rramjet · « **Reply #14 on:** August 30, 2013, 11:17:50 AM »

"No need on 2.0 or engine with solid lifters."

So the need to ensure rocker face alignment with valve tip is not a concern with 2.0?

Sounds like I might as well plan on cam bearings while I'm having head work done as well as line boring the bearing towers.

I was thinking about shaving a little of the head for a little compression boost, maybe .020. I have seen the warnings about shortening the head bolts if I do this. Thinking about going the stud route. Heard there are no alignment pins for the head/gasket so these would help as well as making it easier to reinstall the head.

Anything else I need to consider?

Pintosopher · « **Reply #15 on:** August 30, 2013, 07:18:19 PM »

Any Change in the Valve seat depth or Rocker arm post/ adjuster base on the head will affect the contact patch of the rocker arm "slipper " and the engagement of the valve tip to the rocker arm. Camshaft base circle diameter can alter this too. In the end you have to have All of the head components carefully matched to assure correct relationship throughout the entire rotation of a cam lobe. Any machinist/ builder that doesn't recognize these factors on the Ford 2.0 and 2.3 , doesn't deserve your money. To grasp it all, get ahold of a Copy of Dave Vizard's Book "How to Hotrod the 2.0 litre OHC Ford." and you will see the limitations of the engine and where building one for maximum performance, helps with a understanding of the design. This book is out of Print from HP books, but you might score one if you dig deeply enough.
Good Hunting,
Pintosopher

amc49 · « **Reply #16 on:** August 30, 2013, 07:31:08 PM »

I have 90% of that book committed to memory.

Available online in .pdf form for free but copyright issue means you have to find it yourself. Found another one too in the two minutes I spent just now looking for links. 'How to Powertune Ford SOHC', completely different book.

I was referring earlier to simple stock valvetrains, not custom one off race setups, which are totally different. Also, the process I mentioned has nothing whatever to do with rocker face alignment, per se. It is simply to prevent the motor running like crap when a deep valvejob is done on car, tips extend and then the hydro lash adjuster on 2.3s then limits out to hold the valve open. Then mechanic throws the whole ball of wax at car trying to find out why it won't run. I saw it happen several times back in the seventies, the old school guys simply thought the valvetrain would take care of itself. Many of them were not smart enough to pre-collapse the adjusters anyway, if still at the last running position they then hold valve open when re-used after the valvejob. I take a simple C-clamp and squish all of them down at rebuild time, that way they are at zero bottom and then can expand to fit in the first couple minutes the engine runs. May rattle a bit but in a minute it's gone, and then motor runs fine.

jeremysdad · « **Reply #17 on:** September 01, 2013, 09:14:17 AM »

Go ahead and do this when you have your head redone. Once, and done.

http://www.burtonpower.com/parts-by-category/engine-components/camshaft-parts/std-camshaft-kit-sohc-pinto-2-0-cam-followers-pipe-camsohc20kit.html

rramjet · « **Reply #18 on:** September 01, 2013, 11:50:48 AM »

Thanks. Was thinking about that. Pretty good price considering it includes the followers and oil pipe. Need to find out what the shipping runs.

jeremysdad · « **Reply #19 on:** September 01, 2013, 12:24:33 PM »

Stupid expensive, but very fast. DHL pWns UPS/FedEx/USPS.

lol If I recall correctly, shipping was almost the same as the part price. But worth it...once, and done.

Here, listen to this, and Happy Labor Day!!!

74 PintoWagon · « **Reply #20 on:** September 01, 2013, 12:36:00 PM »

Gotta love the FE.

jeremysdad · « **Reply #21 on:** September 01, 2013, 01:32:57 PM »

Quote from: 74 PintoWagon on September 01, 2013, 12:36:00 PM

Gotta love the FE.

2nd gear burnouts are awesome.

74 PintoWagon · « **Reply #22 on:** September 01, 2013, 02:03:37 PM »

Quote from: jeremysdad on September 01, 2013, 01:32:57 PM

2nd gear burnouts are awesome.

Badazz to the max..

rramjet · « **Reply #23 on:** September 02, 2013, 12:10:07 AM »

"Stupid expensive, but very fast. DHL pWns UPS/FedEx/USPS. lol If I recall correctly, shipping was almost the same as the part price. But worth it...once, and done. "

Well even with the shipping shown on their website it's still cheaper than just the cams I've found stateside. It does look like they don't keep them in stock with the wait they mention.

amc49 · « **Reply #24 on:** September 02, 2013, 11:54:09 AM »

Aw com'on, put some carbs on that 'stang. I see what look like lowly 4224 660 centersquirter s on there. Centersquirter s zoop, they load up the back barrels too much. We ran a single 4 bbl. 1300 cfm Dominator on our AMC 401 street car, and twins on the race car.

Second gear burnout? You gotta be kidding. That motor lugged down when he did it. One of our AMCs would have broke tires loose and rpm skyrocketed past redline instead of lugging down. We could do an exact dupe of that 'stang burnout in FOURTH gear.

I had a 8.4/1 compression 304 (rated at 150 HP LOL) out of a station wagon that ran in the high elevens in an AMX, it could do second gear like that 'stang. Actually better, I used to irritate the GM boys next door to our shop by sidestepping the clutch at 6000 or so and then doing a 100 foot tire smoking burnout past their garage at around 7500 rpm the whole time in 2nd. Everybody would come out and laugh at the huge cloud of tiresmoke.

rramjet · « **Reply #25 on:** September 02, 2013, 11:11:12 PM »

Well adjusting the valves made a vast improvement in idle and low speed operation but still had a surge at 60 mph and higher. It would go away if the engine was under load like climbing a hill. Finally figured out the vacuum advance is bad. It will move momentarily with about 5 lbs of vacuum but won't hold it, the vacuum bleeds off quickly. Disconnected and plugged the line from the carb and no more surge. Assuming it was a lean surge with the possibility that the advance was also moving back and forth.

So far it appears that a vacuum advance unit is unobtainium although I have located complete rebuilt distributors for a pretty reasonable price.

Anyone else run into this?

jeremysdad · « **Reply #26 on:** September 05, 2013, 02:01:20 PM »

Glad just adjusting the valves sorted most of your issues. It is possible that somewhere in it's previous years/owners, your head may have already been machined with hardened seats, which would be cool for you. I don't know of any way to know for sure other than tearing it down to look.

Regarding the distributor, mine originally had the dual-advance distributor, but somewhere over the years, the spout for the advance had been broken off, so I had the retard spout running ported vacuum cause I didn't know any better. Of course, it ran funny, but this was done while I was chasing my tail diagnosing the condition caused by receding valve seats, so I doubt it really made much of a difference.

I got a reman single advance distributor from O'Reilly for something like 50 bucks.

74 PintoWagon · « **Reply #27 on:** September 05, 2013, 02:28:33 PM »

And they're still $50, just picked up a reman over the weekend.

rramjet · « **Reply #28 on:** September 05, 2013, 03:38:55 PM »

Funny, the thought that maybe the head had already been done crossed my mind but I'm going to pull it anyway just to be safe. Opportunity to replace the timing belt and tensioner while I'm at it.

Found a local machine shop who's owner used to race Pinto's so feel like I will be in good hands.

74 PintoWagon · « **Reply #29 on:** September 05, 2013, 03:50:15 PM »

Lucky deal finding a place like that.

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Author Topic: 2.0 Valve adjustment (Read 12056 times)