Packard Forum Index » General

Hello Folks,
My 356 Engine on my 1940 180 is running hot and without removing the engine out of the car I was planning on removing the Starter, Water pump, oil filter canister, maybe the distributor to help in removing the freeze plugs. The Radiator and water pump have been rebuilt. Then I will flush it with water and then add Diluted Muriatic Acid, followed with water and baking soda to neutralize the acid, Then re-flush the system with lots of water to clean out the system.
After all done, put back together to see how the engine performs temperature wise.
I have never done this and was wondering if anyone out there has. Apparently Muriatic Acid is nasty stuff.

Thank you Roberto

It will not be feasible to use muriatic acid after you remove the freeze/core plugs and other items you mention. The acid/water you pour in the thermostat outlet will run out the dist tube and freeze plug openings instantly.
If it is to have any effect it must sit a while.

After the freeze plugs are removed the water jacket goes down over 1 inch. Scrape vigorously with a screwdriver and a coathanger, I found it full of sediment even after using a presssurewasher

I'm not a chemist but in reviewing the internet there are pros and cons. Most importantly it must be in a well ventilated area and goggles/gloves/ appropriate mask must be used

I'm not a straight 8 Packard guy, but wouldn't it be a good idea to remove the water pump and the brass water distribution tube and flush as well?

Im not 100% sure but I don't think the 356 has a water distribution tube.

The 356 uses the same water dist tube that the other eights made thru 54 used. Someone mentioned in another post that some of the senior pre 1940 eights did not have one.

O_D has advised using oxalic acid for cleaning many timeshttps://packardinfo.com/xoops/html/modules/newbb/viewtopic.php?post_id=162991#forumpost162991 IIRC in some of the discussions believe it was mentioned that was Packard approved and the same item as one of their radiator treatment products. I would think might be a gentler and safer treatment than muriatic acid.

Quote:

Andy (AJS) mentioned it -> here.

All sixes 37-50 used a brass water dist tube.

All 120's 35-39 used one

All straight 8's 40-54 used one

In summary, all monobloc sixes and 8's 35-54 used one, no earlier or later cars did

So called muriatic is HCL or hydrochloric. A better choice is H2SO4 sulfuric used heated. However, I would get the distribution tube out first and flush the block with water because acid will accumulate in any residue and stay there. Cleaning the cylinder head with the acid will probably have a greater impact then the block and if you make a mistake the only loss is a cylinder head.

Good Afternoon...When we went through all of the issues regarding overheating, with our 1949 Deluxe, 'Miss Prudence',we also found that the distributor condition, bearings, advance springs and vacuum advance play a big part in a happy Packard engine. Due to wear, and modern fuel, your timing might well need to be advanced a bit from stock. If you search, you can find much discussion of this subject. Easy does it. Ernie

Gentlemen,
I appreciate all the good information and its good to know I have other options. I will continue to investigate this subject to see what I will decide. I am leaning towards the safer of the solutions at the moment.
Thank you