Jeremy_Brault Posted October 25, 2015 Share Posted October 25, 2015 I have a 93 RD with an E-7 400. It started to intermintately pushes the antifreeze out of the radiator. Then it will run for a month and do it again. Now it wont quit. I also noticed that during this time it had seemed to have alot of pressure in the radiator, even if it sat for a week still had excess pressure. So we installed a new waterpump and water pump housing (local dealers idea) but did not work. Then we removed the drive coupler from the compressor and tied the antifreeze lines together so we eliminated the compressor. Still no cure. So next we pulled the heads, and the head gasket was blown out in the left rear corner of #6, but not to a water jacket. It has oil shmoots on the firewall, Is that my problem? if so why did it blow out there? We also noticed that the heads are cracked in three places all the same, from like the exhaust valve seat towards the center. Is that common, or the problem? Any help would be great thanks Quote Link to comment https://www.bigmacktrucks.com/topic/42342-e-7-400-coolant-system-issues/ Share on other sites More sharing options...
wheeler73 Posted October 26, 2015 Share Posted October 26, 2015 The cracked heads are definitely a problem and will cause your complaint. Check you liner protrusion before you put the new heads on as I have seen issues with the liners not being the correct height and causing the head gaskets to fail. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/42342-e-7-400-coolant-system-issues/#findComment-308801 Share on other sites More sharing options...
turckster Posted October 27, 2015 Share Posted October 27, 2015 Cracking in the areas described is common with excessive coolant temps. 210-215 degrees is max coolant temp for these engines. Another thing to look for before installing reman heads is make sure you have the correct fire rings for the type liners. Some early e-7 engines had stepped type fire rings for the liners. Later they went to flat type fire rings. If the engine had been overhauled any time then they would have installed the newer type liners but, it's better to be safe than sorry. I'll try to find the service bullitin about the two type liners and post it if you're interested. Quote Link to comment https://www.bigmacktrucks.com/topic/42342-e-7-400-coolant-system-issues/#findComment-308948 Share on other sites More sharing options...
Dirtymilkman Posted October 27, 2015 Share Posted October 27, 2015 I'd replace liners too just in case theres cavitation. I had a E7 427 with just at a million miles, we pulled the heads and the liner protrusion was to low. Damn things still had the cross hatches in them and no ridges. So if you got it opened up you might as well go the extra step and be good for the long run. Quote Link to comment https://www.bigmacktrucks.com/topic/42342-e-7-400-coolant-system-issues/#findComment-308959 Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.