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1984 engine knock

 
Old 02-28-2019, 01:37 AM
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renchjeep
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Default 1984 engine knock

Bought an 84 a couple months ago. Nice car, very clean, 69k original miles, auto trans. Engine had been rebuilt about 250 miles before I bought it. I was told that the oil pump had "failed" and taken out a couple bearings, so a full rebuild was done. Sounded OK on test drive and inspection. Later I noticed a bit of a knock kinda noise when revving in park or neutral, on decel. Having heard rod knocks many times in my life, it doesn't sound like a rod knock. I have no idea what oil was in it, but I did an oil and filter change with Valvoline Synthetic 10w30 at around 500 miles to get any break-in oil out, as was recommended by the rebuilder on the receipt. Nothing odd like metal shavings or metallic stuff in the oil that came out. Noise persisted. Figured maybe the rockers needed to be adjusted while running, as the engine was built by a shop, then installed by someone else (previous owners nephew and a mechanic friend of his). Put on my old faithful cut-out valve cover, did each side, back off each rocker till clacking, tightened til quiet, one slow turn further. Some were indeed out of adjustment, but afterwards, noise remained. I am guessing it was just a crappy rebuild. No warranty, of course, and it seems like the shop that rebuilt it is now out of business. So, now looking for a good running gen 1 small block to replace this one with. I am finding a few locally, but all have left side dipstick location. Can I use a left dipstick engine in my 84? And I am assuming that my Cross-Fire intake will work with any gen 1 small-block heads. Is that correct? I would rather do an engine swap than try to rebuild this original engine again. Thanks in advance for any help you guys can give me.

Chris
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Old 02-28-2019, 04:49 PM
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zachaeous
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The camshaft in the replacement engine would be a concern for the vacuum necessary for the crossfire. The dipstick most likely could be worked around in some manner with the availability of options for sbc out there.

I was going to buy a GM new crate engine for my 84 and they told me that they did not have one that they would recommend for the 84 because of the camshaft and vacuum issue. I ended up buying a used block and built an engine myself.

The correct block for the 84 is #14010207 I found one used on ebay. Good luck on your repair.

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Old 03-01-2019, 03:49 AM
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They do make vacuum pumps if you want a better camshaft. That sound you hear is money comming out of your wallet.
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Old 03-02-2019, 01:24 AM
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Today I bought a good used crate 350. My old boss (who is an excellent engine builder) told me the story behind this engine. It was yanked from a 67 Chevelle that his buddy was selling because it had a small tick when cold, went away once warmed up. His buddy did not want to try selling a Chevelle for a good chunk of change with a cold tick. The Chevelle was sold and shipped off to Japan with a new crate engine. This slightly used crate engine looks like a low-mileage unit, very clean inside, no slop in timing chain, etc. The left dipstick deal shouldn't be too much of a hassle to work out. For 200 bucks, I have scored another bullet to plug in while I rebuild the original 84 engine, and do it properly this time, unlike the previous shop who rebuilt it. My rebuild will most likely include a slightly hotter cam, a bit of head port and bowl polishing, 1.6 roller rockers, and a bit of work to the Cross-Fire intake. Wish me luck!
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Old 03-02-2019, 02:02 PM
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I have a driver's side dipstick. Car runs fine.
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Old 03-02-2019, 03:17 PM
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renchjeep
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Originally Posted by 383vett View Post
I have a driver's side dipstick. Car runs fine.
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Old 03-02-2019, 03:19 PM
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..... I put a driver's side dipstick in mine and now it pulls to the left … …..
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Old 03-04-2019, 03:34 PM
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Originally Posted by renchjeep View Post
This slightly used crate engine looks like a low-mileage unit, very clean inside, no slop in timing chain, etc. The left dipstick deal shouldn't be too much of a hassle to work out. I have scored another bullet to plug in while I rebuild the original '84 engine, . . . and a bit of work to the Cross-Fire intake.
You might be better off fixing your "new" engine than rebuilding (again) your '84 engine. If the previous builder was as bad as you say, that engine may not be rebuildable! In addition, those '84 heads (casting #624), are pretty poor, and probably not worth doing the work on them you are thinking about. What are the casting numbers of the heads on your "new" engine? The Cross-Fire intake manifold is okay,but saying it's a "bit of work" may be an understatement! But it's definitely worth the work!


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Old 03-04-2019, 03:42 PM
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Originally Posted by C409 View Post
..... I put a driver's side dipstick in mine and now it pulls to the left Ö Ö..
That's a great idea for your circle track car!!!

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Old 03-04-2019, 04:01 PM
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Originally Posted by C409 View Post
..... I put a driver's side dipstick in mine and now it pulls to the left Ö Ö..
did you check to see if itís hitting the ground?
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Old 03-04-2019, 09:11 PM
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Originally Posted by 383vett View Post
Did you check to see if itís hitting the ground?
I was wondering how you took that picture for your Avatar!! Do you have a p/n for that XL dip stick?

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Old 03-12-2019, 02:19 AM
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Bit of an update. I pulled the intake and oil pan on the used crate 350 today, all looks fine, very clean. Definitely a low-mileage unit. I will replace the timing chain set with a Cloyes double-roller, and of course reseal the timing cover and oil pan with the best Fel-Pro gaskets. I also had a look at the head casting numbers. 333882's. Late model, lightweight heads, larger valves, hardened seats, decent flow, but prone to cracking under high-heat conditions, according to the info on the video provided by Hot Rod Roy. So....thinking ahead a bit, and wanting to run cooler than the 238 that the fans kicks on at, considering a 195 stat and maybe 205 or so fan switch. I do still need to pass smog here in Kommiefornia, so do you guys see any issue with passing the smog test running a 195 stat and 205-210 fan switch? All other smog equipment is on the car and functioning properly. Thanks in advance!

Oh, one more thing: The knock sensor on the right side of the engine block. There is only one place to mount it to on the crate engine, and it goes into the water jacket. Is the knock sensor supposed to go into the water jacket? I though the later-model engines I have worked on had it threaded into a blind hole on the side of the block.

Last edited by renchjeep; 03-12-2019 at 02:25 AM.
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Old 03-12-2019, 06:17 PM
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My '84 passes CA smog tests with flying colors. I built my engine about 15 years ago, and I've forgotten what t'stat is in it! I think it's a 180 deg. I have a CTS in my radiator fan control with a 215* on/200* off, which works fine ( ACDelco D1855B ). The fan cycles on and off at idle, and does not run when I'm at highway speed. Engine temp stays at about 200-205*.

With a 195* t'stat and a 205* CTS, your fan might never turn off, because the CTS turn off temp is lower that your normal engine operation temp.

The knock sensor screws into the same tapped hole in the side of the block that has been used as a water jacket drain hole since 1955.

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Old 03-13-2019, 12:59 AM
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Thanks, Roy. I will try a 190 stat and the same fan switch you used. The knock sensor....I imagine those threads should be sealed with liquid Teflon? Or is there another recommended sealer?
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