Hello Everyone. Doing my last try before I give up. My dad owns a 1989 Brougham V8, 307. He bough the car with engine problems so he decided to but re build it, we order all the pieces from US and a guy in my country did all the job, happens that after turning on the car there was some noises, so he said it was carburator issues, as a result we bough a new carburator and he installed but the noise this time was worse, so my dad told him to check again the engine because of that noise, after opening it some of the push rods were damage. So again looks like the same problem the car has when we bough it, what could be? I dont want to waste more money, I know nothing about cars, my dad knows something that is why Im trying to help with information, English is not my native language but Im doing my best. Please your guidance, I bought the car for him as a gift since he always want it a cady but this engine problem is driving me crazy. Thanks in advance and let me know if need some pictures happy to share... The rest of the car is on great conditions I dont want to lost it.

 

Welcome. From your description, it sounds like the valvetrain was assembled improperly allowing "slop" (large enough tolerances that the pushrods were loose, made noise and got bent). It is hard to tell where the assembly of the engine went wrong, likely either something changed that made the pushrods too short or the rockers were not shimmed properly. Photos of the damage would help diagnose the cause. I'm not the expert here by any means, but others here know these motors inside and out and will likely chime in soon with recommendations.

 

You mentioned that you bought a new carburetor.. Did you buy a CCC Quadrajet, mechanical Quadrajet or aftermarket carburetor (i.e. Edelbrock or Holley)? Provide pics of the top of the engine and the new carburetor.

 

 

Those pictures I posted are when they were assembly, after what happened I can not take pictures because they remove the pieces and took it to repair place, the push rods that were damage they throw them away.

 

This is the new carburator

 

What pictures?

 

I saw the pics. With the Edelbrock carburetor did you change the distributor as well (to a 4 pin HEI or points distributor)? If not, your car is in LIMP mode essentially.

 

I dont know why the images are not uploading let me try again

 

Let me ask my dad about with what distributor they run the test, the distributor that is going to be installed would arrive to my country at the end of this month and it is this one we purchased https://www.jegs.com/i/Proform/778/6...02/-1#tab_kits.

 

I'd suggest a compression test to determine the internal engine condition before doing any more work. If the compression is good continue to fix it. If the compression is bad it will never run well regardless of any external repairs or modifications.

 

they did the test with the old distributor the car had it , a distributor with electric advance, that distributor was with the old carburator Rochester. Let me know thanks

 

what is the range of compression for this kind of engine V8 307? My dad told me that did not do the test because everything was new, it is a complete overhaul. Let me know any questions so I can ask him. Thanks in advance.

 

An overhaul that isn't running properly is a good reason to do a compression test especially after bending pushrods. All PSI #'s should be within 10% of each other, in other words a 10% maximum difference between the lowest # and the highest #. I'm guessing about 135psi but let's see if another member can confirm the target psi#.

Anyone?

 

x2 on doing a compression test. 135 +/- 10% would be perfect.

https://classicoldsmobile.com/forums...on-test-79166/

That distributor will work fine.

 

Compression ratio on the 307 is 7.99:1, or nominally 8:1. Compression test for 3.8L or 5.0L gas engines according to GM (CSM) is take all the plugs out, hook up the gage to the spark plug hole, crank it over at least 4 "puffs" worth and take the reading. It doesn't specify a "normal" reading, just that the LOWEST compression cylinder must be within 70% of the highest, and no case should any cylinder be less than 100 psi. Example: If you have 145 on the highest cylinder, your lowest cannot be less than 102. Which is dangerously low to the 100 psi mark. If your highest is 135, your lowest still can't be less than 100. Using the 70% rule, that would be 95 psi, which is below the threshold for GM. I'm not too sure I like their method of acceptability, but that's what GM has to say about it. I'm still of the old mindset of having all the cylinders within 10% range of each other.

Issue is, that doing a compression test now, on a rebuilt engine (assuming engine was prepped and new piston rings installed, the rings haven't set yet. This will give you extra pressure loss until the rings seat, so there's that. But doing it as a comparison across the cylinders can be beneficial to see if there's any of them dropping out.

 

What kind of noices, can you describe them?
A bad carb or distributor would have nothing to do with bent pushrods.
Was the camshaft and/or the pushrods replaced during the rebuild?

 

Yes everything is brand new!! any guess?

 

piston and rings were fitted to .020 there are some images above where you can see that number, let me know

 

Hi Carol, where are you located? The reson I ask is to know if your mechanic has much experience with american engines or if you can find one that does.
I'm assuming that the noise is mechanical like a loud ticking or knocking. Ask your mechanic if he has an engine stethoscope so he can pinpoint where the sound is coming from. A long screw driver or piece of hose can also be used. Once you find out where it comes from it will be easier to find the cause. Good luck!

 

Can you find the part number of the pushrods that were used ?