last week we determined that some of my oil leak problem was 4 bolts holding my carb intake to the heads, so we applied sealant and 3 stopped leaking. on Saturday I thought i'd address the last one that did not stop leaking, so not only did I add sealant to it again, I decided to use a longer bolt because the other 3 were longer. I used a 1.5" bolt but it turns out the other were probably 1.25", the max that should be used. so anyway, monday go for a drive but power is weird, I figured it had to do with engine being cold and I just changed the fuel filter and thought maybe there was some starving going on, but 30 minutes later I decided to go back home and figure out what was wrong. anyway, yesterday I pull the valve cover off to find a cracked valve rod that I retrieved from the head with a magnet on a stick but I had to remove the intake to put the lifter back in the head. anyway, it is all back together but it revs ok in neutral but under load it is either valves or knocking. what you think? anyway, why does a guy with so little mechanical prowess own a 914, who the hell knows. i'd like to think the noise is due mostly to timing cause I of course had to pull the distributor. and I never put a tdc mark on my flywheel or crank balancer, need to, asap. I first thought it was vacuum advance problem but vacuum is pulling thru hose.


https://www.youtube.com/watch?v=tfKEa1-W0XQ


video is being loaded, pls check back and comment. pls pls.

any local mechanic should be able to help diagnose that....
Its a chevy v8....so look for an older guy that works on trucks ...they know.

rich

Man I would just replace it with something more reliable like a 6

check compression on that cylinder ,may have a bent valve....timing,
advance till it pings under accel then retard, so it does not..............smblk chev no rocket science..

I agree with Rich find a local Chebbie guy. It doesn't get anymore basic than a SBC.
So you used a too long manifold bolt and broke the pushrod.
Get a shorter bolt.
1) You need to replace the broken pushrod with another that has the same exact length.
2) Once pushrod replaced you need to set the clearance between the rocker arm and the Valve spring retainer.
3) Then find TDC on cylinder 1
4) Install your distributor so the points just open at TDC
5) Set your dwell on the distributor if it has points
6) Set your timing at idle with a timing light with vacuum disconnected and capped.
(usually 8 deg BTDC)

I've heard of push rods bending, but not breaking. Looks like your long intake manifold bolt was interfering with the push rod. You don't say the you replaced that, but I'm assuming you did . . . It's kind of hard to tell what we're listening to. It should be quiet if the lifter is properly back in it's place and the rocker arm is adjusted properly.

If the bolt was interfering with the push rod, I'd had to think where the metal filings went. It's all pretty simple stuff, but don't drive it anymore until you find out what's up.

Since at least that valve with the broken push rod is closed, I'd perform a compression test (all 8 cylinders) as it sits now (no intake manifold, disconnect fuel pump source or wire, remove spark plugs).

If compression in all cylinders are within spec, it sounds like it's just a matter of careful visual inspection, replacing the broken push rod, reassemble engine, adjust the valves, then run engine. But that's being optimistic. It could also be less so.

It's possible that the longish bolt interfered with the path of the push rod, perhaps rubbing it until it failed. Confirm on forums catering to Chevy owners.

The internet and the world has all the info you need for the tasks at hand.

Sherwood

Good advice go to Autozone and loan out a compression gauge. Bet you got a bent valve.
Bob

shit.. sound like the consensus is I may have a bent valve.. shit.. did I say shit already? damn.

The problem is: You don't have a 914 engine.

Do you have a engine rebuild shop locally? Then chances are you can get this done in a day if you pull the head yourself. Take it down to the engine shop, they can pull the valves and likely have the correct valves in stock to replace.

Get a scope, pull the spark plug and look at the piston, if it hit you'll see.

My bet its timing/vacuum leak. Bent valve??? I doubt it. In fact, I would eat brussels sprouts for a week if its a bent valve. Wiped cam maybe.

Start with the dumb stuff. The firing order 18436572. 5 and 7 get crossed up all the time. Sounds like its really advanced. Does it start exceptionally well. Spin the distributor counter clockwise (to retard it)till she just starts to slow down the engine. put it in first and stand on it. Improvement? spin a bit further. Improvement? you get the jist.

I you get it running well enough to get it over to me, we can tune it, check it over, and put a timing mark on it. I'm around all weekend. Second exit on the western side of the bay bridge.

Steve

PS if you do a compression test make sure you didn't collapse the lifter setting the lash.

Don't feel bad Jim. I'll bet there were a thousand guys that didn't pay attention to which hole the short bolt went into (the one right in front of the #1 cylinder wall) when removing the alt bracket on a 327. Any old timers here remember that fiasco. When I saw your pic I remembered that when I was a kid I had that intake off 3 times one weekend. The last time was to get my mom's paring knife that I left sitting on top of the lifters. Scared the shit out of me when I started it.
Jim, most of us have fuched up more times than we care to remember but that is part of the learning process. Keep on keeping on.

Chevy's wipe cams pretty easy. Doesn't take much. BTDT with a new cam and solid lifters. It's also fairly easy to collapse the hydraulic lifters during adjustment. Other than that they are tough to destroy.

Oh, if you don't know already, don't use the rubber intake gaskets. Toss them and just use a thick bead of permatex ultra black.

Click to view attachment

The truth is the engine,is a write off,total rebuild.

Many questions.
Because you have metal in your oil.
Murphy lives inside engines.
Did you compare the new pushrod's length with the others?
Did you remove any metal from the pushrod's guide hole?
Did you inspect(microscope)the flying lifter?
Did you inspect the valley for metal fragments?
How badly damaged was the stamped rocker arm?
Any nicks on the valve tip?
Appears to be a bone stock iron head,with an ally intake and headers,and I presume,a stock cam.
Factory valves and guides?
What head castings are they,compression and squish?
How many hours old is the cam chain and sprockets?
Any indications of knock or ping under load?
What are the compression and leakdown readings?
Have you had the valve seats scoped?
Have you ever pulled the pan to check rod and crank clearances?
What is your oil pressure and temperature,idling while hot?
Any sign of scoring in the bores?
Have you pulled a piston to determine running clearances and wear?
Many questions,for a sbc lump,the beauty is the price to fun ratio.

https://www.google.ca/webhp?sourceid=chrome...-8#q=find%20tdc
https://www.google.ca/webhp?sourceid=chrome...+aluminum+heads
https://www.google.ca/webhp?sourceid=chrome...t%20chevy%20350

The truth is we have to make mistakes to learn "do not do that again",at times,that can be very costly.


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don't know what's worse, bent valve or cam wipe which I never heard of before now. geez. wish I have more tools here, engine stand, torque wrenches, timing stuff, and know how, most importantly know how. thanks guys for not laughing at my pain

If the intake manifold bolt put enough pressure on the pushrod to cause it to break, there will likely be some sort of problem, damaged lifter/cam lobe, or bent valve because the valve couldn't close, or both.... As far as 'wiped cam' that means the cam lobe is worn out or will give less lift. You can run on that for a while. Not optimum, but not unacceptable either. You could have also destroyed/collapsed the lifter which I assume is hydraulic or bent the rocker arm . THIS is your best hope.

I agree with the comments above, check/replace the lifter, replace the pushrod, and do a compression check. IMO, if its a damaged cam lobe, DRIVE it..... Take your time, Save your $$ plan a build, do it right. If a bent valve well.....

The good thing: Your working on the most common V8 engine on the planet. The second good thing is they are easy to work on.

Start systematically. You can first check the valve lift with a simple metal ruler. First check to see you have not set the lifter too tight. At bottom dead center see if you can just spin the push rod with your fingers. I think you can go 1/4 turn tighter but don't take my word for it. I haven't built a Chevy for 30 years. Check the internet sites for SBC engines. Just leave the pushrod as is for the test.

Next rotate the assembly through one revolution. Measure the amount of travel from the bottom of the motion to the top at the nose of the rocker.

Then check another exhaust valve and compare. Who cares if your not dial indicator accurate. With the intake on you will at least know if you have enough of a difference to dig deeper into the engine. Lifter or cam.

Ya, Another thing. Watch the bolt that can come in contact with the push rod for the mechanical fuel pump. That will wreck a cam also.

Jim,

How did you set the lash when you installed the new pushrod?

Provided everything turns with no binding once you replace the push rod you should do a compression test before you assemble the intake.
You are looking for that cylinder to be zero or really different from the others .

If you pass that test you may have dodged the bullet of a bent valve

Please remove the profanity from your title. It's offensive.

lol funny guy......

Time to upgrade?

Click to view attachment

Excellent advice, it's a Chevy V8.

Lots of good advice here. Get new pushrod and install Adj valve lash at BDC. Tighten rocketr nut while spinning pushrod with fingers. Stop when resistance is felt . Turn 1/4 additional turn . That is 0 lash.Crank the motor over while watching rocker arms. If the cam is wiped you will see little movement in that rocker arm. Cams are damaged by incorrect break in procedures. If all looks good do compression test. These motors are tough not like the little toy motors the car came with

compression test of cylinder in question #4. the jump to 60psi is with coil wire still on dist cap. i then removed coil wire to dist cap and cranked it again. tried to rent comp tester from advance but they don't do that at my closest store. so I bought one for $29. seems a v8 spark plug is 14mm, go figure.


https://www.youtube.com/watch?v=rnZkafToHug

It's an old Chevy... Put a push rod in, adjust the valve and put it back together.

Make sure you have the throttle wide open on the compression test, if its closed the piston does not suck enough air. Compression seems like it could be ok, I would check an adjacent cylinder to see how it compares, to give you a base line.

Also as others have said make sure you install the new push rod correctly. Solid or hydraulic cam? Hydraulic cams have no valve lash setting.

Are you running all stock components (heads, rockers, springs). Sometimes after market valve train components will need custom length push rods.

Do you think your noise could be lifter tap? or do you hear more of a 'knock'?

You need to compare that reading with other cyls. I haven't checked compression on a GM SB in years, but I seem to remember 90 was perfect, 60 or below not healthy. You should kill power to the coil and fuel pump for this. Also, make sure you are checking the compression with throttle wide open.

[/quote]

You need to compare that reading with other cyls. I haven't checked compression on a GM SB in years, but I seem to remember 90 was perfect, 60 or below not healthy. You should kill power to the coil and fuel pump for this. Also, make sure you are checking the compression with throttle wide open.
[/quote]

Yeah kill the power to the coil, I once just pulled the main wire off the coil and it zapped to its own power feed wires and fried the coil! on top of that it was a computer car and fried the dang ECU!!

I know you're learning... but just FYI.. that's not typically how one would do a compression test. As others said, you don't want that thing firing up (as it almost did). Kill the power to the coil and turn it over several times with the throttle wide open. On a /4, it would be easier to just pull all the spark plugs to allow the engine to crank over nice and easy without compression in each cylinder. On a V8, you'll just leave them in, but it will crank slow.

I believe you'll have a different reading than you're seeing currently with a couple more revolutions of the engine. Keep at it, you're on the right track...

Yep.

If it blows,a near new wrecker is available for less than 1K.
Almost as disposable as shoprags.
One other thing,be certain the pressed in rocker stud was not damaged,inspect the rocker's bowl and stud's ball,make sure the rocker's face is not marred.
These stamped rockers can bend in some interference circumstances.
If the cylinder will hold air,screw in an airhose plughole adapter and release the spring keepers.
Don't lose them,use a magnet,or rag to keep them from falling.
Make certain the cylinder is at TDC,you don't want the valve to fall into the hole.
You can now check the run-out and clearance of the valvestem.
With 0.0025" wiggle or runout,the max wear has been reached.
With a worn guide and poor seals,the engine will blow blue smoke and foul plugs.
A scope of the piston top will show heavy carbon buildup.
Once you find the heads beat,check the shortblock's bottom end.
A new set of heads is on the getlist,because the aluminums are cheap enough.
Check your local craigslist,they're hot commodities.
Have fun,it doesn't get cheaper than this.

As others have said, disable ignition and fuel pump. Then keep the throttle wide open while cranking. You need to crank motor about 4 times and see the psi then. Also notice roughly how high the compression climbs on each crank compared to other cylinders. I would also remove all of the spark plugs during testing for most accurate reading. Good luck.

Brett

I don't know why you all keep talking about a bent valve. That doesn't seem likely. He didn't have any backfiring so the valves would be closed just fine.

He put in too long a bolt that interfered with the push rod. Metal in the oil, change it. Check the lifter and take a look at the cam lobe for excessive wear. I doubt you have much of a problem.

thanks guys for all the great advice. I am taking my car to rightpedal's place on sunday to button it up, provided we don't find anything new. tomorrow I plan to drain the oil, look for metal in it, and will redo the compression test. thanks again

Drag a big time magnet through the old oil to find metal. Cut the oil filter open to find same!

Good tip. Best wishes.

If it all goes bad,here is a cheep way out:
https://delaware.craigslist.org/pts/5399241755.html

those are good deals but I need a pre 1986 engine as my renegade stuff is for pre 1986 I think? hopefully I won't need a new engine this time around. i'd also prefer to get going on my 1975 suby conversion project for when gas prices go up again.

http://www.renegadehybrids.com/914/SBC/SBC.html

ok, drained my oil and removed filter. checked removed oil with a small magnet and felt like I did not find any metal in it. pic of drained pan that I should have cleaned very thoroughly before draining my oil into it.


https://www.youtube.com/watch?v=luRqmw2sd14

I did this exact same thing 25 years ago (too long of a bolt on the intake) with exactly the same end result. It was on a fresh rebuild and the push rod broke within 10 minutes. I replaced all of the pushrods, got the right bolt, and the motor went 180k without any issues before the van it was in was sold - and we beat the crap out of it. I don't think we even changed the oil after the initial damage happened.

Obviously you need to look for any additional damage, but based on my situation, that motor is far from toast unless you see other damage.

Good Luck!

I have a fresh '76 400 with increased compression and a Voodoo cam, but that's kind of a truck motor. I'm working on a '66 327, and there's a '65 283 waiting.
Just in case.

what i'd really like is a low power/high rev sbc to better match a stock 914 trans that does not have a flipped H 5th gear. at 70mph my engine is spinning at about 3,000rpm. 75mph is about 3200-3300, which I do not mind. but I think a typical sbc needs to be shifted at 4000 to be some what gentle on it, 5000 is pushing it and 6000 is asking for trouble I think. maybe I just need a rev limiter set at 4500. oh, and ideally, it would sip gas too

https://www.youtube.com/watch?v=OsGqmOQus6Y


How to.

(WYIT)

A dab of axle grease will stick the keepers to the valve on reassembly.
Use a magnet to pull them out.
Do TDC for each cylinder,because it's easy and keeps murphy outasite.

/

LS1 with an Audi trans is a pretty darn nice swap.... Many members have done this.

283 Chevy will rev

What about a 4.3 V6? Everything bolts up just like the 350. Same engine, just 2 cylinders missing.

More of a torque motor but still a good one. For the good power and high revs, go with the 327 block and the 283 crank... viola, the 302!

I used to have a built 350, revved to 6500 all the time, no problems. Its all about the valve terrain. Need good valve springs so the valves don't float.

A stock motor should be good for atleast 5500, I'd recommend looking up your particular engine if you can.

With a 914 I'd mostly be concerned with going around corners and not getting oil, its not a dry sump like a six is. The oil has to be scavenged on the bottom of the motor. Probably only a real concern with a track car, that will see higher g forces. But make sure your oil is always full.

I really like the idea of a v6 for the extra space you get in the engine bay primarily.