Jeep Enthusiast Forums banner
281 - 300 of 346 Posts

·
Premium Member
Joined
·
2,117 Posts
Maybe this?? .......The front bolt on the driver side (No. 11 on attached torque sequence image) needs high temp thread sealer or equivalent since it goes through the water jacket. Does seem far removed from where you are seeing coolant on the starter however might be the source and migrating back.

JS
 

Attachments

·
Registered
Joined
·
399 Posts
Discussion Starter · #282 ·
Maybe this?? .......The front bolt on the driver side (No. 11 on attached torque sequence image) needs high temp thread sealer or equivalent since it goes through the water jacket. Does seem far removed from where you are seeing coolant on the starter however might be the source and migrating back.

JS
When I checked this bolt, it did loose a little torque. I'm wondering if the sealant I used did not work properly or got contaminated? Is there any harm if I take that bolt out and re seal and put back in, or do I risk warping the head?
 

·
Registered
Joined
·
1,637 Posts
Adding a new item to the list tonight... head gasket.

While trouble shooting the reverse light issue I had after my test drive, I noticed a liquid on the starter. My first thought was oil which turned out to be coolant. How did I know? I had to revert to the taste test. Surprisingly enough I learned two things, 1. I don't have Covid, 2. the sweet taste gave me a idea it was coolant.

I check around the head and at the back of the engine, passenger side, I feel water. I also noticed that the radiator system builds pressure fairly quickly which is odd being as cold as it is in Ohio. On that note, the radiator also "pukes" out coolant when the thermostat opens without a cap.

All torques were double checked and there seemed to be no loose head bolts. So, maybe the compression in cylinder 6 is blowing into the cooling system past the head gasket? I need to do some additional tests before I tear it down.

View attachment 4133062
Just to ask the question - Are you sure fluid is not coming from above the area in the pic, and pooling along the gasket, on its way down?
Perhaps a heater hose above with a loose clamp weeping an occasional drip?
Perhaps dripping more forward, and air around the engine when running, blowing it back to this point then leaking down?
These engines do slope back lower at firewall, so thinking its possible the coolant can come from almost anywhere forward of the pooling point, and not be noticed if very slight leak.
Just thinkin'
 
  • Like
Reactions: JoonHoss

·
Premium Member
2011 Jeep JKU
Joined
·
11,092 Posts
From memory, the rear valve cover bolt (for after market cover) on my 83 also went into the water jacket, and required sealant.

Just something else to consider

Hoss
 

·
Registered
Joined
·
399 Posts
Discussion Starter · #286 ·
Just to ask the question - Are you sure fluid is not coming from above the area in the pic, and pooling along the gasket, on its way down?
Perhaps a heater hose above with a loose clamp weeping an occasional drip?
Perhaps dripping more forward, and air around the engine when running, blowing it back to this point then leaking down?
These engines do slope back lower at firewall, so thinking its possible the coolant can come from almost anywhere forward of the pooling point, and not be noticed if very slight leak.
Just thinkin'
I'm going to check for leaks again tonight. I need to fix the valve cover gasket first because I messed it up. I couldn't find any fluids coming from the front of the engine but I think a closer inspection is needed for sure.

I was also digging around for information on the torque specs for head bolts. I bought ARP bolts and I'm pretty sure when I bought the bolts I had to send one pack back because a few bolts came up short. Anyways, I checked their website for the 7/16" 4.2L bolts, they say to torque to 70 ft-lbs. But if you look at the Jeep service manual, it says torque to 85 ft-lbs and to service recheck them between 80-90 ft-lbs. I know I went by the ARP instructions but I'm questioning if the gasket is compressed enough.

@JoonHoss, I'm going to check that tonight. I cant recall the valve cover bolt running into the cooling jacket but I will check. The head has 84 stamped on it an I have an aluminum valve cover but I did not have to modify the existing head to accept it.

Thank you both for the questions and suggestions!
 

·
Premium Member
Joined
·
3,008 Posts
Is this a freshly rebuilt engine? If so what head gasket did you install. Was the head & block re-surfaced during overhaul? it sounds like it is a rebuilt engine since you installed ARP head bolts.
 

·
Premium Member
Joined
·
2,117 Posts
deer slayer,

Head bolt torque is not necessarily a static number for a particular engine/head. It can vary based on the bolts manufacturer, length, diameter, and stretch of the specific bolts. Lubrication used during installation and torquing is also an important factor in torque values. If you installed ARP head bolts (a good thing BTW) and did so to their specifications, I would follow their guidelines for their bolts on the 258 head bolts when removing and reinstalling the one bolt which may need a revisit due to thread sealer.

Just to say, the front bolt on the driver side needs Loctite 592 high temp thread sealer or equivalent.

If you have any questions, I would call ARP. I have found them very helpful regarding torque recommendations.

Good luck in getting it worked out.

JS
 

·
Registered
Joined
·
399 Posts
Discussion Starter · #289 ·
Is this a freshly rebuilt engine? If so what head gasket did you install. Was the head & block re-surfaced during overhaul? it sounds like it is a rebuilt engine since you installed ARP head bolts.
Yeah I had this engine machined in 2018 and the short block was assembled by the guy who did the machining and myself. It was a joint effort at his shop so I could learn the process.

The head gasket was a Felpro 8778-PT I believe. It would have came in the master gasket kit I got from Napa.

Just to say, the front bolt on the driver side needs Loctite 592 high temp thread sealer or equivalent.
If you have any questions, I would call ARP. I have found them very helpful regarding torque recommendations.
This is the route I'm taking this weekend. I'm going to call today to see if they have any input and then I'm going to drain the coolant from the engine head and loosen the bolts to re torque.
I'm assuming I can use a head gasket that got a little wet? Does anyone see any long term problems with this?
 

·
Premium Member
Joined
·
3,008 Posts
I think you have a good plan. Always loosed and re-torque head bolts when you are performing a re-torque on a fresh engine. Some will simply put the torque wrench on, and push in the tightening direction, and it will click, that does nothing to improve the situation. You have to loosen them first, and then re-tighten them until the wrench clicks at your torque setting, as you described above, in order to do it correctly. When you do it this way, you are actually loosening and then re-clamping the squeeze provided by the head bolts. (a true re-torque)

Im a little confused on whether or not you have a thermostat or overheating issue. I suggest you remove the thermostat for initial break in, and initial driving, it is easier to get the system full of water without air pockets without a thermostat installed.

I know it’s cold this time of year in Ohio, and you need antifreeze, but I suggest you fill it with water for your initial startup and break in driving, just make sure you drain it, or add coolant when you are finished for the day.

After you do what you described above, If you start it up, and suspect a slight water leak/seep from the head gasket, don’t be afraid to try a bottle of “Alum-seal” radiator stop leak product. I suggest you go buy a bottle before you start it again, and be ready to use it. It works, and it will not clog your radiator like other products. I have put it in race engines that had been machined perfectly and still suffered a seeping head gasket on initial startup & break-in. It will stop minor seeps in the head gasket permanently from my experience.
Product Font Screenshot Advertising Cuisine
 

·
Registered
Joined
·
399 Posts
Discussion Starter · #291 ·
@devildog80 , @Axhammer , @STJP , @JoonHoss

Do any of you know if there are supposed to be centering dowels on the 84-86 engines? This may sound like a dumb question on my part but I do not recall seeing any dowels when I pulled the engine out of the frame... In my early posts from a few years ago I have pictures of the head and block separated and I see no dowels... I essentially used the bolts for centering.
 

·
Premium Member
Joined
·
2,117 Posts
@devildog80 , @Axhammer , @STJP , @JoonHoss

Do any of you know if there are supposed to be centering dowels on the 84-86 engines? This may sound like a dumb question on my part but I do not recall seeing any dowels when I pulled the engine out of the frame... In my early posts from a few years ago I have pictures of the head and block separated and I see no dowels... I essentially used the bolts for centering.
When I pulled the head on my 1985 258 there were no centering/alignment dowels.

JS
 

·
Premium Member
Joined
·
3,008 Posts
That’s the way my 4.0 went together, no dowels for cylinder head alignment to block. I’m sure if they were required Chrysler would have made the improvement, when they revised the 258 into the 4.0.

On my 0630 head, the only holes that could have been used for a dowel, are empty on my head. My 4.0 block has no corresponding holes, so I don’t think they were used on your 258.
Automotive exterior Motor vehicle Automotive engine gasket Audio equipment Automotive tire
Automotive tire Automotive lighting Gas Font Tints and shades
 

·
Registered
Joined
·
1,637 Posts

·
Registered
Joined
·
399 Posts
Discussion Starter · #296 ·
After some research here at work and talking to a co-worker who does drag racing, there are two head gaskets available by felpro. There is a 8778PT and a 8169PT. My engine is dated in 1984 by the engine vin. I saw some people are using the 8169PT but if I look up any head gasket for 1985, it claims I need a 8778PT gasket.

I'm unsure of what I have but I am still going to re torque the bolts first. to see if I have any in consistencies. Its the only thing I can do before I pull the head. With no guide pins, I could be a few thousands off on a coolant jacket. lol the more I dig into this, there are so many different variables that could be at play lol
 

·
Premium Member
1984 Jeep CJ-7 Renegade
Joined
·
10,186 Posts
I believe the difference between the two FelPro Head Gaskets are the bolt sizes for the head. Either 7/16" or 1/2" diameter. FelPro's 8778 PT is for 7/16" bolts and the 8169 PT should be for 1/2" bolts. As far as I know, 1986 was the year that head bolts were switched back to 1/2" diameter.
 

·
Registered
Joined
·
399 Posts
Discussion Starter · #298 ·
Over the weekend I decided to pull the head. I couldn't live with not knowing what the gasket looked like. I didn't want to get 50 miles down the road and blow a gasket or cause damage I couldn't see. Overall, I did not see a blow gasket or anything of that nature but I believe it is a clamping issue. When taking the head bolts off, some bolts seemed to have a decent torque to them but others seemed very easy to break loose. Also, Looking at the gasket, I can see where the gasket is clamped harder in some areas.

I'm going to assume I made the mistake of not double checking the torque after the first few heat cycles. Also, the bolt that requires thread sealant seemed to fail. There wasn't a lot of it on the threads so I believe I didn't clean up the threads very well.

I also started some research on the bolts. The factory head bolts I have are two lengths. One set of bolts have a threaded stud on the hex head, which are longer. The others are just hex head bolt. The longer bolts are a straight shank that measures roughly .4335" and then necks down to 7/16-14 thread. The ARP stud kit has a smaller shank size of .3895". I'm wondering if I could have been misaligned along with the clamping force issue. With no alignment pins. I can see that the original bolts could help align the head

The head gasket doesn't come in for another few days but everything is cleaned and ready to be installed. I am going to borrow a certified calibrated torque wrench from my work and follow the proper procedures for installing the head and bolts.
 

·
Registered
Joined
·
399 Posts
Discussion Starter · #299 ·
Head gasket came in the other day. I cleaned everything up for a new gasket and followed ARPs grease instructions and what not. Except I did not follow their torque specs. I went to the FSM specs, which is 85 ft.-lbs. ARP recommended 70 for the 7/16 bolt. I also used a calibrated torque wrench from my work and found that my wrench was about 15% off (less) of the calibrated value. I mean a Harbor Freight torque wrench is just to get you by. But up to a 10 ft.-lb difference could be the difference between the issue I had or success so I'm more confident now we are fixed up.

I went with the FSM 85 ft-lbs because I felt the other gasket did not have good clamping impressions for 60-70 ft-lbs. Besides, if a standard bolt from 1985 was torqued to that, why would ARP bolts not be able to withstand another 15 ft-lbs? We can get into the metallurgy of it, but I can do that when I have more time... I don't want to dig out my books from school

Rockers go in tonight and hopefully I have a running engine, again. retorque will follow after a heat cycle.
 

·
Registered
Joined
·
6 Posts
Metallurgy certainly comes into play but in this case I think you've doubled up in increased clamping force by splicing 2 different sets of instructions. While I dont have a FSM in front of me I believe that torque spec is based on dry, non-lubed bolts. But you mention greasing the bolts per ARP's specs. Greasing the bolts before torquing them will substantially increast the bolt tension for a given torque value per this video
. So by lubing AND using a higher torque you could push the bolts beyond their yield point or have crushed the gasket. Now, ARP makes good stuff and I suspect the bolts are probably OK, but just wanted to point out that double dipping on the torque could be just as bad as too little torque in certain situations. (I don't post here much but do a lot of reading on this forum and happen to work with bolt torque at my day job).

Sent from my SM-G930V using Tapatalk
 
281 - 300 of 346 Posts
Top