I have been in this situation before and my suspect is related with your Timer job service. It is recommended you need to suspend Search Service application using below before you install CU update otherwise your search might get corrupted.

$ssa = Get-SPEnterpriseSearchServiceApplication -Identity Search Service Application 
Suspend-SPEnterpriseSearchServiceApplication -Identity $ssa

The following steps hopefully resolve your issue

You might want to try clear configuration cache

use the powershell script in link below: https://gallery.technet.microsoft.com/office/Clear-Configuration-Cache-d55bcba9

Remove search again using powershell.

 $P = Get-SPServiceApplication -identity [GUID of Search Service Application]
 Remove-SPServiceApplication $P -RemoveData

STSADM command if Powershell above not working

 stsadm -o deleteconfigurationobject -id [replace with GUID of enterprise search]

Note: Deleting using stsadm command above, you might need to remove SearchDB and Search Application Pool.

It also worth to check if there is an OrphanDB using the following code

$OrphanDBs = Get-SPDatabase | Where {$_.Exists -eq $false}
#clean any Orphans DB
Get-SPDatabase | Where{$_.Exists -eq $false} | ForEach {$_.Delete()}

Once Search service deleted, i have come another problem where i always get timeout when creating Search service either using powershell or Central admin GUI. Then i decide to remove the server from the farm and then rejoin the farm which reinstall the services.

I have been in this situation before and my suspect is related with your Timer job service. It is recommended you need to suspend Search Service application using below before you install CU update otherwise your search might get corrupted.

$ssa = Get-SPEnterpriseSearchServiceApplication -Identity Search Service Application 
Suspend-SPEnterpriseSearchServiceApplication -Identity $ssa

The following steps hopefully resolve your issue

You might want to try clear configuration cache

use the powershell script in link below: https://gallery.technet.microsoft.com/office/Clear-Configuration-Cache-d55bcba9

Remove search again using powershell.

 $P = Get-SPServiceApplication -identity [GUID of Search Service Application]
 Remove-SPServiceApplication $P -RemoveData

STSADM command if Powershell above not working

 stsadm -o deleteconfigurationobject -id [replace with GUID of enterprise search]

Note: Deleting using stsadm command above, you might need to remove SearchDB and Search Application Pool manually.

It also worth to check if there is an OrphanDB using the following code

$OrphanDBs = Get-SPDatabase | Where {$_.Exists -eq $false}
#clean any Orphans DB
Get-SPDatabase | Where{$_.Exists -eq $false} | ForEach {$_.Delete()}

Once Search service deleted, i have come another problem where i always get timeout when creating Search service either using powershell or Central admin GUI. Then i decide to remove the server from the farm and then rejoin the farm which reinstall the services.

I have been in this situation before and my suspect is related with your Timer job service. It is recommended you need to suspend Search Service application using below before you install CU update otherwise your search might get corrupted.

$ssa = Get-SPEnterpriseSearchServiceApplication -Identity Search Service Application 
Suspend-SPEnterpriseSearchServiceApplication -Identity $ssa

1. You might want to try clear configuration cache use the powershell script in link below: https://gallery.technet.microsoft.com/office/Clear-Configuration-Cache-d55bcba9

2. Remove search again using powershell

   $P = Get-SPServiceApplication -identity [GUID of Search Service Application] Remove-SPServiceApplication $P -RemoveData

3. If powershell not working then try using the following stsadm -o deleteconfigurationobject -id [replace with GUID of enterprise search]

Note: you might need to remove application pool and search database manually if using step 3 above

Once Search service deleted, i have come another problem where i always timeout when creating Search service either using powershell or Central admin GUI. Then i decide to remove remove the server from the farm. Then rejoin the farm.

I have been in this situation before and my suspect is related with your Timer job service. It is recommended you need to suspend Search Service application using below before you install CU update otherwise your search might get corrupted.

$ssa = Get-SPEnterpriseSearchServiceApplication -Identity Search Service Application 
Suspend-SPEnterpriseSearchServiceApplication -Identity $ssa

The following steps hopefully resolve your issue

You might want to try clear configuration cache

use the powershell script in link below: https://gallery.technet.microsoft.com/office/Clear-Configuration-Cache-d55bcba9

Remove search again using powershell.

 $P = Get-SPServiceApplication -identity [GUID of Search Service Application]
 Remove-SPServiceApplication $P -RemoveData

STSADM command if Powershell above not working

 stsadm -o deleteconfigurationobject -id [replace with GUID of enterprise search]

Note: Deleting using stsadm command above, you might need to remove SearchDB and Search Application Pool.

It also worth to check if there is an OrphanDB using the following code

$OrphanDBs = Get-SPDatabase | Where {$_.Exists -eq $false}
#clean any Orphans DB
Get-SPDatabase | Where{$_.Exists -eq $false} | ForEach {$_.Delete()}

Once Search service deleted, i have come another problem where i always get timeout when creating Search service either using powershell or Central admin GUI. Then i decide to remove the server from the farm and then rejoin the farm which reinstall the services.