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Adjusted valves and broke valve cover bolts, advice on replacing?

I assume by .07 you mean .007. Don’t worry about the adjustment being at .007. That’s tighter than spec but not tight enough to damage anything. When someone mentions tight exhaust valves I always assume 0 or less than zero lash.

The Honda techs are correct. The lash should be inspected every 30k miles. The factory recommendation is ill-advised.

Yes that’s correct. That’s one of a few downfalls I have with Honda, I don’t understand why they didn’t use the newer style “self adjusting” type. Thanks for your reply. I appreciate everyone who took time out of their day to ease my mind and point my in the right direction.

It’s not just Honda. Over the years a number of other car manufacturers such as Subaru, VW, Nissan, Toyota, and others have used mechanical valve lifters instead of hydraulics.

We had a guy brings a Subaru in once that would barely run. The story behind it remained murky but it is believed that he was irritated by the subtle tick of the valve lifters and adjusted them down to zero to shut them up. The engine did not run long before burning out all of the exhaust valves and valve seats in both cylinder heads.

Both heads were so far gone they were not even salvageable and had to be replaced with new. The sad part was that this was done on a new car. It only had 7k non-warrantable miles on it.
The owner didn’t complain about the repair cost so we assume he knew he had botched it.

Oh wow! I did not know that those autmakers use mechanical instead of hydraulics. I am just an avid do it yourselfer with some basic mechanical knowledge from school days. I do not like the “tick” either but tappy valves are happy valves as they say. I wonder why those automakers chose mechanical over hydraulic? Is it cheaper or more reliable?

As far as hydraulic lifters go, it’s a mixed bag. It varies by year, engine, or model. At one time car makers recommended 15k miles inspections. It then evolved into 30k miles and then near infinity. The 100k or more recommendation is ill-advised.

As for why, solid lifter engines have a crisper rev although the difference may not be noticeable.
The hydaulics are less maintenance of course.
The solids also offer a bit more power at high RPMs. Again, the difference may not be noticeable.

Just as an FYI, the old Chrysler Hemi engines were solid lifter engines. Harley Davidson started using hydraulics in 1948 on their overhead valve models; way before it became fashionable.

Nice, thanks for the info. Import cars (at least to me) seem to have a crisper rev now that I think about it.

One last question for you if you would please. Would you happen to know how many ft.lbs those valve cover bolts are torqued to, the bottom half? My computer is going wonky and I don’t have a paper manual. The only thing I can find is 16lbs, but that’s for the k20 heads. I ask this because that source also said the bolts were 8mm but they are 12mm.

The parts window guy at the dealership should be able to answer that one. Their references include torque values. Note that in your case you’ll have two values, one for the shouldered studs to hold the camshaft caps on and the other for the final nuts to hold the valvecover. Be sure to get them both from the parts guy.

It’s scary how many of these I’ve seen snapped off. People seem to think that the nuts that hold the valvecover on have to be as tight as possible to seal the valvecover gasket. They don’t. They need only be tight enough to stay seated. The valvecover gasket is seated by the dimensions involved in the assembly, not by overloading them with the nuts.

It’s also possible that people try to stop valvecover gasket seepage by more tightening of the valvecover nuts, not realizing that they seat onto shoulders on the studs.

Are you sure you’re not confusing bolt thread diameter with head (wrench) size?

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Thanks for the heads up, in my case I had installed a set of spark plugs and had the torque wrench set at 13lbs. I simply forgot to reset the wrench. I am not a person of excuses but it sure didn’t help that my mom and friend was blabbing in my ear. I feel like such a dumba$$. The funny thing is I removed them with a small 1/4" ratchet. I absolutely knew better but it didn’t register soon enough.

LOL, been there, done that! :yum:
Sincere best.

I don’t think so, all I know is an 8mm socket will not fit over the “head”, a 12mm does but is slightly and I mean slightly loose.

LoL, Thank you for your input! Much appreciated!

An 8 mm bolt might well use a 12 mm socket. The bolt “size” is the diameter of the threaded section, not the size of the head.

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Yeah I know that, I’m not sure if they was talking about the diameter or the head size. I just assumed head size. Looking at Honda parts online it calls the acorn nuts 6mm, but the head actually takes a 10mm socket. They probably were talking about diameter instead of head size. I never deal with diameter unless I am replacing a bolt that I know I can get at the hardware store, so I really had no concern for diameter since I already knew it was a specialty item from the dealer. Thanks for your input though. I appreciate everyone’s time and knowledge and patience with an average diy-er.

I had John Muir’s repair manual for my old VW Rabbit, and he always gave the bolt head size in the instruction, which was more convenient than if he gave the bolt size. Who cares what the diameter of the threaded section is when you are fixing your car, you just want to know which socket to use next. You have to know the actual bolt size (the threaded section diameter) if you want to buy a replacement bolt tho.

Exactly my friend! Was your rabbit a good car? I never owned one but always was fond of them.

It was definitely a car … lol … good or not depends on what all you expect in a car. The main problem I had with the Rabbit was the fuel system. And that was really my doing, in that I bought one of the first mainstream fuel injected cars, a late 70’s Rabbit. The Bosche K-Jetronic system wasn’t electronic, totally mechanical. Modern FI uses high pressure throughout, and modulates the fuel delivery by how long the injectors are held open electronically. The Rabbit had no electronics in the FI system, the modulation of the fuel delivery was by varying the fuel pressure to the injectors. Not a good idea, in retrospect. The part that regulated the injector fuel pressure had very tiny clearances & would clog up and stick if any fine grit at all got past the fuel filter.

I should add to be fair that if you wanted fuel injection in the late 70’s, that was about it as far as the econobox segment. Modern Rabbits – I think they sell them under that name, either that or Golf – use modern electronic fuel injection so I’m sure that’s no longer an issue.

But at least I knew what socket to use when I took the fuel system apart to clean it … again … lol …

@aftermath999, speaking for myself and other mechanics I’ve known; none of use a torque wrench for certain things. Those things would include valve cover bolts, spark plugs, and so on.
A “feel” is developed and it’s much safer than a torque wrench. Many torque wrenches may be accurate at higher torque numbers but down low they can be off a bit. This presents a problem when a 3/8 or 1/2" torque wrench is used for lower torque setting.s

I’ve got a very accurate 1/4" drive German made torque wrench and I seldom ever use that.

As for the old VW Rabbits, they had their issues. The biggest one was the cantankerous CIS fuel injection system.
They also had their weird issues such as the faulty radio antenna grommets. During a heavy rain water could run down the cable, inside the car, and onto the fuse box. The water would short the starter solenoid wiring and away the starter motor would go.
This was a big problem if the car was a manual transmission left in gear with the park brake not set.

There was one towed in once in which the female owner had reported it stolen. It had rained the previous night and the VW had taken off on its own. The cops found it a block away against a utility pole with a dead battery and fried starter.

Another oddity was when the gas tank vent would screw up. Engine vacuum would suck the tank near flat; much like blowing up a paper bag and then inhaling until it’s flat. People were wondering why they were running out of gas after filling it up and why it only took 3 gallons to fill an empty tank.,.,… :smile:

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Well I finally got around to replacing the bolt, and as luck would have it or lack of experience / and or preparation I did not count on needing thread locker for the bolt. I took the bolt out and the bottom half had been covered in thread locker. Unfortunately I only had blue loctite on hand and I think it was old but I used it anyways because I am unsure of which type to use but now I am concerned that the bolt will vibrate out and cause some major damage.

Renew bolt again, this time with the proper threadlocker product.