200 engine with coolant leak at block / head

[Crosley]

A minor coolant leak on the driver's side near #4 cylinder area. The white lines a couple of inches long as the water seeps out the head gasket seam. As I recall I used a FelPro gasket from Mike.

If I pull the head for new gasket, I am thinking I should mayb add larger camshaft , new springs on the valves. Not go too wild, just setup from the 274/274 - 110* hyd camshaft I have now.

Mayb mill the head more, already milled .050 during engine build, Mayb install some flat top pistons this time. Dish pistons on the engine now.

 

[ludwig]

That leak condition is very common on the I6. There was a guy who posted about it maybe a year or two ago. He was a fleet engineer for some company that used small I6s in their vehicles. He said that it has to do with the differential heating and cooling at the siamesed exhaust port of the head at 3 and 4 and the block. His solution was to rout a small channel around the block and head and fill it with a graphite string gasket in addition to the head gasket. It was more sophisticated than I am explaining. Bottom line is that it is a design shortcoming with this engine.

 

[Mustang_Geezer]

A minor coolant leak on the driver's side near #4 cylinder area. The white lines a couple of inches long as the water seeps out the head gasket seam. As I recall I used a FelPro gasket from Mike.

If I pull the head for new gasket, I am thinking I should mayb add larger camshaft , new springs on the valves. Not go too wild, just setup from the 274/274 - 110* hyd camshaft I have now.

Mayb mill the head more, already milled .050 during engine build, Mayb install some flat top pistons this time. Dish pistons on the engine now.

Tony,

Real common problem! It happened a couple of times on my old motor and the second time it happened (After I pulled the head and replaced the head gasket) I just dumped some stop leak in it.

Up to you but as you say it would be a good time to do some more upgrades! :mrgreen:

Later,

Doug

 

[chad]

That leak condition is very common on the I6. There was a guy who posted about it maybe a year or two ago. He was a fleet engineer for some company that used small I6s in their vehicles. He said that it has to do with the differential heating and cooling at the siamesed exhaust port of the head at 3 and 4 and the block. His solution was to rout a small channel around the block and head and fill it with a graphite string gasket in addition to the head gasket. It was more sophisticated than I am explaining. Bottom line is that it is a design shortcoming with this engine.

love 2 hear the "more sophisticated" on that...
And/or ways to prevent the short coming from ever developing problems. Is it unavoidable if running the motor at normal operating temps beyond 100K miles? My '68 170 seems to be leaking and has about that many mi. (I assume) and would like to prep a rebuilt '69 250 before installing if possible...

 

[Gene Fiore]

Yep...these motors are notorious for leaking coolant between the head and block on the driver side. Have you tried re-torqueing the head?

 

[xctasy]

Ford Australia fixed the problem, I think in 1965 with the XP engine. They reduced the inner hole sizes to stop the US passenger side leaks. 33 Noo Zeeland bux, and I use it on my 3.3 liter 1982 Mustang.


This gasket is the ACL AP630MT on an early C1 144/170 head with the stock size water holes. It was pulled off my 1966 200 cube Falcon engine. Its listed as a later Aussie replacement gasket.

See http://qiklink.acl.co.nz/Modules/Catalo ... listtype=0



All the Australasian Ford Falcons got this new type of head gasket as a replacement, Ford Parts now lists it as a replacement for all log head and 2V 250 Falcon engines

See viewtopic.php?f=3&t=66024

 

[Gene Fiore]

Interesting....I wonder what the compressed thickness is of that gasket?

 

[xctasy]

Down here, about 41 thou compressed I think.

It's not a great item to reduce compression on a 250. Our 250's down here had 25 thou deck to block short fall and small chamber heads, so they used thicker than the steel gasket depth.

There used to be some 62.5 thou composite gaskets, not sure if they are still around.

 

[JackFish]

Sometime during the 70's Ford changed the torqueing sequence for the head bolts.
The earlier manuals have the first bolt to be torqued up on the passenger side, while the later manuals have the first bolt to be torqued up on the driver side.
I'm not sure if this has anything to do with the problem but it's worth a try.
I did it this way and have no leaks.
Now my valve cover is a different story....

 

[Crosley]

Not sure if I correctly explained my slight leakage. It is on driver's side near #4 cylinder spark plug area. Couple of small white lines of seapage. No leaks on exhaust / intake side of head.

I run distilled water with Water Wetter and a can of water pump lube / corrosion resistant additive. I forget the brand name of the additive I installed.

I have not retorqued the bolts since the original install and recheck . OEM bolts were re-used on head install

 

[xctasy]

The Aussie gasket is also rather wide under the line of bolts that are used for the stock iron header, and I remember Mike saying it can cause some interferance if a 250 2v head is used with a stock iron header on US block. Since the iron header won't match the centre ports of Aussie 2V head anyway, its not really an issue. Some steel headers have bigger flanges, and the Aussie head gasket can foul the bottom bolts.